I bought almost everything from eBuyer too - get out of my head!
Yup, just plug in the mini DisplayPort and the USB and everything will work OOB with OSX. Make sure the magsafe connector is out of the way and not shorting anything! Windows may be slightly trickier, but google it enough and everything should work. The display itself is fine without any extra drivers.
I love the display myself, but if you haven't bought one yet, just check that you are happy with:
1. The short cables. The screen is mainly designed for MacBooks so you may have to keep your computer on the desk if you don't shell out for some tedious extension cables, not available directly from Apple.
2. The glossy screen - many complain of reflections, just like the Macbook Pro and iMac. Some also say that it means that it can't be used for applications where colour accuracy is vital because of this. Colours are otherwise fantastic though.
3. The refresh rate. This type of screen is made for sharpness and high quality colours, as well as vast screen estate, so it's not really a gamers display. 12ms is really pretty slow, and if you are very sensitive you might notice it. I've tried Portal, and have found it perfectly acceptable, but YMMV.
4. The price - it's worth it and actually stands up pretty well to other 27" displays, especially when you figure in the usefulness and elegance of on-board audio, webcam and USB hub. But it's still a lot of money. Know someone in the NHS or similar organisation happy to buy it for you? You'll save at least £70 direct from Apple, without having to resort to ramraiding.
Don't let me dissuade you from the purchase - it's a great screen. It's slightly assuaged my guilt at building a hackintosh, and I also love the idea that with my wireless keyboard and magic trackpad, almost everything on my desk is stock Apple.
I'm not sure if there is a way to PM people on this board, but if there is, feel free to send me a message, especially if it's a UK-only question.
David