I've owned this phone for a little over a week now and really loving it so far. The build quality is fantastic, love the feel of the back and the rest of the device is solid. I've owned a few Blackberrys in the past including the original Bold and the 9700, the original Bold was always my favourite qwerty keypad of all the phones I've owned(I've owned a great many qwertys from various brands, they're becoming something of a rarity these days though) but this is definitely the best of the best IMO. I've read reviews and many comment there isn't really much need for physical qwerty's now that the touch screen virtual keyboards are so good, while I agree they're leagues better than they used to be I still feel you can't beat having actual keys to press when hammering out a message.
The BB10 OS is a real joy to use, not quite up there with MeeGo from the Nokia N9, but at the same time it has its similarities and since Nokia decided to ditch MeeGo and move over to WindowsPhone then BB10 is certainly one of the better operating systems for Nokia fans that aren't fans of WP to move on to. Everything runs nice and slick and I'm yet to have any lock-ups or crashes as yet. The Amoled screen is beautiful to the eye, although the blacks aren't quite up there with Nokia CBD found on devices such as the E7 or the 808, put the phone onto the clock mode while on charge and at night you'll discover the Q10 background is still kind of lit and not completely black as you might expect, minor detail though.
Battery life is very good, I have been a bit spoiled having come from the Symbian powered 808 which could easily see me through 3 days of fairly intense use(despite it's 1400mah battery!) but with the Q10 I can comfortably get through 2 complete days on a full charge, with I would say above average use, better than most smatphones out there and far better than my wifes iphone 4S. It's great that the battery is removable meaning you can carry a spare if you're away for a weekend, rather carry a spare battery than need to take a charger with me.
The camera is one area of disappointment for me, I know it isn't a key feauture of the phone and let's face it, us Blackberry owners are used to making a sacrifice when it comes to the camera we're gifted with, but still I would say it's average to good at best. Don't get me wrong, it's miles better than the old EDOF camera's and it can take some decent enough pics, but most seem to have this washed out bright haze to them(as if the lense is letting in too much light). I'm hoping the camera can be improved with a future software update because if it wasn't for this light blur the camera would pretty good.
As for Blackberry World, it's plenty good enough for me even in its current state, most of the stuff I need is on there and the catalogue and Q10 compatibility is improving all the time. The best new discovery for me is Mireo DON'T PANIC, an offline navigation app that uses TomTom map data, it runs beautifully on the Q10's screen and is far far better than the default maps/navigation app, highly recommend the free 7 day trial(oh and don't forget to switch it to night view to take advantage of the power saving black backgrounds bring to Amoled screens, I used it for 5 hours the other day and the battery was still going!).
All in all a brilliant device and will likely continue to improve with future updates. If you miss qwerty devices and hate these new massive fabula type phones then give the Q10 some serious consideration, it's a beauty :-)