Yeah, if you do a side-by-side comparison of the HTC Evo and the HTC Incredible, you will find that there are just some few differences.
1. The Evo's screen is 4.3" and the Incredible is 3.7". If you actually do a physical size comparison, you only gain about a 1/4 of an inch with the Evo's screen. However, the Evo's screen isn't AMOLED, which the Nexus One and Desire have. AMOLED is much more power efficient, has much brighter colors, is just overall capable of being brighter and the contrast ratio is MUCH higher. The Evo doesn't have this type of screen. So, that's a +1 for the Incredible.
2. The Evo is a 4G phone. 4G means "fourth generation." Sprint decided to go with WiMAX as their 4G technology of choice. However, WiMAX through Sprint is only found in 11 states, currently, and even in those states, it's limited to the few major big cities in that state. So, doesn't work everywhere, not even close. The Incredible is still 3G. Verizon is using LTE technology for it's 4G technology but won't roll it out completely until early next year. LTE is said to be the future mobile data standard, WiMAX will more than likely quickly be outdated.
3. The Evo films in HD. Probably not 30 fps (frames per second), because the phone is so small. So, that means that in all honesty, while it WILL be in high definition, the quality won't be anything like what you seen on television or on a Blu-ray disk. As far as we know, the Incredible only films in SD (standard definition) which is 720x480p. That's what we call "DVD quality." The camera on the Evo and Incredible are exactly the same. 8 megapixels with a dual LED flash. Identical.
4. The Evo has HDMI output. This means you can output video to your TV or HDMI ready monitor. I could honestly never see myself doing that, but who knows, it might get used a few times.
5. The Incredible has 8GB of onboard movinand shorage. That's fancy talk for " it has 8 gigabytes of built in memory." The Palm Pre has the same feature. The Evo, however, does not have this.
6. The Evo has a front-facing camera. The Incredible does not.
7. The Incredible supports WiFi 802.11 b/g/n. The Evo does not support "n." Which is the current fasted speeds you can get on WiFi.
I BELIEVE that's about it. So, are the phones THAT different? There's some wins and some losses on both sides. Take your pick. There's the best comparison I can think to give.