Although Thinkpads have had some bad press since Lenovo took over from IBM, they've always functioned 100% for me, despite spillages, dog hairs, etc. I currently have a W510 and the W520 looks good: http://bit.ly/JZSZsA. You can push it to 16GB RAM and it can take a 160GB SSD, so it's a pretty good spec, albeit not inexpensive.
BTW, I am at a loss why anyone salivates over a MacBook - the things are more unreliable than Windows Vista. Friends have even been so frustrated that they've installed Ubuntu for the sake of stability and reliability. They are definitely not extreme user machines!