I've just got my 9900 on Orange (unbranded from phones4u). I'm really pleased with it so far - it certainly feels premium and with the improved browsing it's probably the best handset I've owned.
I've always found apps to be gimmicky and the majority pointless. There are some interesting ones available, but for the most part I like to text, call and browse the Internet so this is great. I had an HTC Desire previously and probably made use of 2 or 3 apps so they're certainly not missed.
I was concerned before purchasing that a lot of people have had issues with phones bricking, dodgy trackpads etc. etc. so it was with some trepidation that I fired up my first 9900. Everything seemed fine, but within 2 hours a bright blue line of dead pixels randomly appeared running vertically along the left hand side of the screen. Nothing fixed it so I returned it the next day (having owned it for half a day!) and got it replaced instantly.
This one seems to be free of problems at the moment, although I don't hold out much hope considering how many different problems have been reported! We'll have to wait and see, but for the time being I'm very happy with the 9900.