I watched it. We have a week long stay there in September (our first ever Orlando trip not on WDW property in fact).
Overall these were my impressions:
1. Universal is continuing to improve on their theming and detail work. The Gringott's Vault room they did the presentation from was really interesting to look at.
2. The fellow dressed as a Gringott's goblin who kept shuffling across in back was a crackup. At least, I assume he was really there, and it wasn't a screen projection; the video wasn't HD and he was largely hidden by the speakers so yeah. I found myself hoping they have goblins in the bank as permanent cast members when DA opens - I want my picture with a bank goblin.
3. The Neville kid grew up and totally changed...? Some of those actors have changed a lot, and some still look exactly the same (the Weasley twin actor, aside from the darker hair).
4. The girl who played Luna is an awful lot like her character.
5. The inside of the Hogwarts Express looked as true as could be. The only thing I found myself wondering was how many people they can fit on that train per ride. That could end up being quite the line.
6. The concept art looks wonderful, and I hope the real thing lives up to it. Since they did a pretty good job with Hogsmeade, I expect the London side will be even better, now that they have the confidence to know HP is successful there and some practice at it.
7. I'm glad they are opening an Ollivanders' over in DA. I don't know if they are closing the Hogsmeade one, but a new one in DA that holds a lot more people will be nice.
8. Personally I'm glad about all the shops. I don't want to go into HP land and just ride a ride and leave. I want to hang out and feel like I'm there; having a lot of streets and shops will help that feeling of immersion. The variety of shops seems like it will be good.
9. Leaky Cauldron - I was hoping to see pictures or footage, but all they showed was a clip from the movie. But it will be there for dining, as with the Three Broomsticks. I hope it has a unique and different menu than TB.
10. Florean Fortescue's Ice Cream Parlor - only shown as concept art but yay!
11. They didn't provide many details about the Knight Bus, only to say one would be there - not a ride I'm guessing but some sort of interactive thing maybe. Honestly I was hoping they would turn the Knight Bus into a variable ride simulator like Star Tours (seriously how fun would that be, ripping around London with the shrunken Dre Head as your guide?!

).
12. Glad they are redoing the Hogsmeade candy store. Too crowded and small. Also hoping that spreading the merchandise types out between different dedicated stores helps make it possible to see more of it. Looking at all the Zonko toys and wizarding candy imagined real was part of the fun of IoA Hogsmeade, regardless of whether you bought any of it.
13. Disappointed that they're only adding 2 attractions (the train and the bank) and reproducing 1 existing attraction (Ollivander's). They really should have added 1 or 2 more attractions to DA. They did say they were still keeping a few secrets, and those buildings could be hiding something, I suppose.
14. Gringott's Bank ride. Yay!
15. I expected more "real" photos of completed site work and information than they provided. I'm not sure why they even did this today, except that they have that HP weekend event going on right now and the actors were conveniently in town for it. They didn't really announce anything we didn't already know about - I mean we all knew there was a bank ride, a train ride, the Leaky Cauldron, and of course there would be shopping.
Almost expected a date announcement, but then realized they won't do it for a couple of reasons. First, what if construction delays run them late; and second, they don't want to cannibalize attendance 2nd quarter. I see plenty of people who are booking for June and "hoping". If they put out a date, and it's July, their parks will be much more empty in June because everyone who can easily postpone their trips will postpone, as long as they're not inside costly cancellation windows and such. In light of all that I wouldn't be surprised to only have 30-60 days notice of the official opening date.