I'm throwing in my 2 cents here because I spent a week with the Fascinate and then a week with the Droid X. I went back to the Fascinate, for reasons I'll describe here. I'd better like it (!), as they're telling me at the Verizon store that I'm only allowed one exchange (I bought the first Fascinate at Best Buy).
I had an iPhone 3G on AT&T and was upgrade eligible, but I was getting sick of having a phone that did not work at the office. Simply put, AT&T's 3G coverage just does not penetrate very far into buildings. Go to the window, you get full signal, go to my desk, and it's "No Service." Most of my co-workers have Verizon Wireless and multiple people confirmed at least decent reception in the building, so I made the switch. I picked up the Fascinate at Best Buy, being attracted by the vibrant screen and fast processors (cpu/gpu).
The first thing I noticed about the Fascinate once I started to use it was the "perforated" appearance of solid colors on the Super AMOLED screen. Yes, the colors are amazing, and blacks are truly black because there's physically no light being emitted from the pixel, but the "Pentile" matrix layout of the AMOLED screens (look this up on Wikipedia) does lead to what appears to be an array of small holes in the image. This is especially apparent when you have a large patch of one color, e.g. when reading webpages which are mostly white. Compare this with backlit LCD screens (i.e. Droid X, iPhone) and it means that text looks a bit more jagged on the AMOLED screens. My brother-in-law's HTC Incredible (also with AMOLED, but not Super AMOLED) has this same problem. The AMOLED screen also means that while surfing the web, the AMOLED screens are going to eat more battery power than the LCD screens (due to most of the pixels firing on at full blast because of the white background), while when using specialized apps that force a black background, the AMOLED screens will use much less power. There are battery life benchmarks on the web confirming this. Someone needs to write a web browser for the Android AMOLED phones that forces a black background! Using Kindle for Android with a black background and white text should result in much better battery life than, for example, Droid X or iPhone.
The GPS worked fine at first and then started refusing to lock on to satellites, like all Galaxy S phones are known to do. But the main thing I was curious about was reception, especially at my desk. At my desk at work, when I placed the phone down, I had between 0 and 1 bars of signal, which corresponded to a signal strength of -96 to -101 dBm. This pulled down data (using the Ookla Speedtest.net app) at around 100 kbps or less, not very good but certainly better than "No Service" on AT&T. Occasionally the phone would revert back to 1x and get roughly the same data rate. If I held the phone up in the air with my hand I would get two bars, -90 dBm, and data rates would increase to 500-800 kpbs. Not bad. But I had heard about the Droid X's incredible reception ability, and since I ditched my iPhone (which I did love, by the way) for reception, I'll be damned if I don't get the phone with the best reception!
After quite an ordeal to switch out the Fascinate for a Droid X (Best Buy was out of Droid X's, and VZW across the street had tons of them, BB tried to bully me into waiting for another shipment to arrive becuase they didn't want to lose the sale-don't buy phones at Best Buy!) I had the DX in my hand and could put it through its paces. Immediately I noticed an update to 2.2 (Froyo) was available and I applied it. Half an hour later, the DX was still stuck at the Motorola boot logo and refused to boot. Mind you, I didn't root the phone or anything, this was the official Verizon update! I pulled the battery and the phone finally booted up, and I had Froyo. However, after shutting the phone down again, trying to turn it on quickly again, the phone refused to boot up again. After several hours of experimentation I had determined that the Droid X, on Froyo, won't boot up if it is too hot. This is a serious hardware issue. That night my wife complained about the clicking sound of the physical buttons which of course wasn't a problem with the capacitive buttons on the Fascinate. I mean, with Android, you have to use those buttons often enough that the force you need for the keypresses and the noise detracts somewhat from the whole experience. Also, even with Froyo, I wasn't too impressed with the overall speed or responsiveness of the phone. But onto the most important test-reception at my desk at work.
I was initiallly impressed-the Droid X was showing 4-5 bars of 3G signal (nearly full signal) at my desk! However, when looking at the actual signal strength in dBm (in "Settings") I noticed that the Droid X was pulling down the exact same value-about -101 dBm-and, using Speedtest.net, was pulling down the exact same data rates-100 kbps or worse! Lifting the phone in the air produced the exact same improvement in data rate. So I was forced to conclude that the Droid X really doesn't have any better reception than the Fascinate (inside my company's building is a pretty brutal test of reception!) and that the "bar" indicator is basically lying about signal strength! I also noticed that, in stronger signal areas, the Droid X will display about -68 dBm while the Fascinate will display -86 dBm. I never saw the signal strength go any higher than these numbers on the respective phones (these are the numbers they display for full signal), yet the performance of both phones downloading data on Speedtest.net was similar. We are thus forced to conclude that 1) bars don't mean anything (and we already know this!) and 2) even signal strength in dBm is not the final word on what kind of bandwidth you're going to get.
So, for my final decision, it came down to this:
Droid X:
huge phone with awkward noisy physical buttons
better text readability on screen, but muted colors compared to fascinate
better battery life when browsing the web
no real improvement in reception
no real advantage in speed over fascinate
won't boot up if it's too hot (many others have had this issue-check the forums!)
VZW store tech said many more returns for glitchy hardware with Droid X than fascinate
Fascinate:
Beautiful but "perforated" screen
Faster UI, faster response overall, even considering 2.1 "TouchWiz" on Fasc. vs. 2.2 "Motoblur" on DX
Acceptable reception, seems to be no worse than DX
Turns on faster and more reliably
Much more lightweight and "pocket comfortable"
GPS issue
I decided to return the Droid X and go with the Fascinate for my "final answer." Samsung sells a larger battery for the Fascinate/Galaxy S for those of you concerned about battery life. I resolved the GPS issue by downloading the "GPS Status" app-so far this seems to return my GPS to working order. And my eyes are getting used to the perforated screen. So far, a great phone, and although it's not as polished as my old iPhone, you sure can do a hell of a lot more on it!
It was helpful when I first started out with overclocking many years ago, though.