Since there are no reviews yet I'll offer my first impressions. I've used a couple of PDAs before, but nothing like this. I apologize if pics are not very good. I had to play with different angles to get proper light.
As noted before, it is very light and compact enough to carry around with ease. I actually found it easier to hold than a paperback. Don't need any pressure to keep a book open. At one point between a cat and a 2 year old wanting attention I was forced to hold it and turn pages with a single hand, yet found it not too difficult or tiring. So far I give it top marks for ease of use.
I clocked boot time at 24 seconds. Personally I don't find it to be too long; at least compared to my laptop
I generally don' mind waiting 20-30 seconds, so it doesn't bother me. Unlike laptop and PDAs, you don't switch it off as often so you don't actually need to start it often either. On the other hand it defaulted with a 5 minute auto-off timeout, which I found odd, more suitable for PDAs. I promptly changed it to 15 minutes.
The 1st screen is the Library view that lists reader content. This one is the highest number of items mode. As said before, it doesn't scale so folder support will be critical in the future.
In the lower left corner you can see 100% battery, of course as I only used it for a couple of days now. Charging vis USB was fine, simple. In the lower right corner is SD memory icon for my 1 Gb chip. I still haven't filled the main memory so don't use SD memory yet.