I have one in my pocket and I can say, unreservedly, that it is the most advanced phone on the market at the moment.
The key is the OS- it multi-tasks like it's a full sized laptop and has basically all the functions of one also...plus being Linux you can do/download/install just about anything to it without all the restrictions of the likes of the fruit-plastered phone, the Pre or anything Android.
Oh, and if you want it cheap on a good Vodafone tariff, give the Nokia flagship stores a call- they have it in stock and I got a damn reasonable price, even for an upgrade (theorder.co.uk have them but at ripoff rates and mobilephonesdirect have awful customer service).
GET ONE! You won't be disappointed.