I've been running LinuxMint12 on my work laptop (Dell Precision M4400) a couple months ago. I found the stock interface weird, so I switched to MATE. I'm liking it, it's a little windows 7-ish, but at least I can easily make short-cuts on my desktop unlike the other way. I do have some bugs I have run into:
1) clicking lock desktop on a 2 monitor setup, moves the bottom nav to the left instead of locking - if I click it a second time it will lock
2) right click 'edit menu' on the main menu on bottom nav does nothing. I think that's important to add icons to the menus.
3) If I boot up with the hardware switch on my wireless disabled, flipping the switch does not work. I have to boot up with it enabled.
Other than that it works pretty well. I've been die-hard Ubuntu fan, but I just really hate Unity.
I did install Xubuntu a couple weeks ago on the wife's netbook - I was so tired of the windows trojans/virus issues I had to do something about it. I think I'll give it a try on my next work notebook OS install.
What is everyone else's Laptop Unix OS favorite flavor, and why?