I have no problem with the prices. Although my preferred option would be some sort of month to month rolling subscription, like Paizo offer with Pathfinder. I don't like having to renew. (Of course, it would need to be priced at the 12-month price point; a 12-month minimum lock-in would be fine.)
I also don't have a problem with that being per person. For me, the DI is not really about getting together with my group to play online. It's more about being able to play online whenever I want, almost certainly as an addition to my regular game (and with the added advantage that I might actually get to play once in a while). So that's fine, too.
I have three big concerns with the DI:
1) Will it actually work? If the features aren't up to scratch, it's worthless. If the bugs are too noticable, it's worthless. Frankly, I find Neverwinter Nights 2 a pale imitation of the real thing, being either destroyed by time lag (in the internet game), or destroyed by the lack of interaction (if played solo). The virtual tabletop has to be much much better for it to be worthwhile. (To be honest, I'm happy with a 2-dimensional 'chessboard' representation of the battlemap if it makes the thing run faster. I certainly want fast high quality multi-way audio, though.)
2) Way back when, WotC talked about various limits on the use of the functionality. You could only store 10 characters, you could only use the Virtual Tabletop 3 times per month (might not have been 10 and 3). These limits have to go, or it's a no-deal. (Okay, that really shouldn't be an absolute statement. If they become 100 and 20 respectively, for example, that's as good as removing them entirely. Or, if they offer an 'unfettered' package at, say $5 per month more, that would also be fine. But the existing limits, especially on the VT, are far too tight.)
3) I'm very concerned about the quality of eDragon and eDungeon. Although I was never going to subscribe to get the magazines, I have been using them as a barometer for the health of the online venture as a whole. And what I've seen so far has been shockingly bad. Wizards now have four months to turn this around, because if things continue as they have been, I am simply not interested.