I have had my Lenovo W520 a week now and must say I am very happy with it. I am still hitting the wrong keys a good deal of the time, the only problem being the Fn and Ctrl keys are reversed in position from my old Acer, it is a good job Fn-V and Fn-C does nothing dangerous!.
The keyboard is very nice to type on, a far more solid feel than any previous laptop I have had.
The performance is great, but you would expect it to be good with an Core i& and 16Gb.
But the most impressive thing has been the battery life, a good five hours even running a TFS instance on Windows 7 and having VS2010 and Office open as I do most days. I had not expected that, the battery extender bits seems to do the job very well.
So all in all very happy, seems an excellent desktop replacement, I just need to find the time to get a lab management demo rig onto it to check it out in really bit load.