I'm gonna be honest, if you had high hopes for the HDMI port being useful on this then I'd say you need to re-evaulate your expectations.
I should reevalute my expectation that something on the phone works? Why should I do that?
I pretty much assumed that the HDMI out on the phone was a bid to sell more gadgets to dads with too much money and no knowledge of hardware. At this point, android's not quite ready to be belching out full HD videos to drive large-scale displays. If you want that, buy an appletv or something.
I guess you're smarter than most of us, then. I also assumed that HDMI was put on there to sell more gadgets, but that doesn't mean that it's OK if it doesn't work. Which it sounds like this one does anyways, at least for video you put on it. And one thing I'd like to use it for is to watch a movie on a TV when on vacation, and I'm not buying an AppleTV, and even if I did, I wouldn't take it on vacation with me.
High-end phones have this sort of crap tacked onto them all the time. Back in the day, when cameraphones first came out they had an absolutely bullshit resolution and were pretty much useless. Manufacturers got wise of the fact that their little ploy to draw in folks who thought consolidating two gadgets would be neat, now they're standard. These days you get other crap tossed onto phones - HDMI out, 3d cameras, dual SIM slots, kickstands - that are not fully thought out, only really suitable for any real use by hardcore users willing to dick with their hardware, and basically intended to make their device more appealing in a sea of devices that have similar specs/software. There might be a point in the future where people see the need to hook your phone up to your TV to play video or use apps, but we're not there now - it's a novelty, and it's something that Motorola can use to elevate their kit over other people's hardware.
Yes, it's a novelty, but for it to elevate their handset over others, it needs to be useable, otherwise it will just be a liability. And just because you don't see a need to hook your phone up to a TV doesn't mean other people don't see the need, or at least have the desire to do so.