I’ve reported my experiences on running previous versions of Ubuntu on the Thinkpad X60. Here are the notable updates with Hardy Heron:

• Wireless: Ubuntu dropped the closed source ipw3945 driver from their restricted packages repository, instead, opting to use the iwl3945 driver that’s included in upstream kernel sources. Unfortunately, the version that gets shipped with the kernel is way out-of-date and doesn’t work well. Or in my case, not at all. The solution is to grab newer drivers from the compat-wireless project. They have a build system that can overlay newer drivers on top of an existing kernel module directory. I tried a snapshot from April, and it worked fine for me. After a reboot, the card came up and worked fine through the NetworkManager.
  One remaining gripe with the wireless is that the hardware kill switch only works half way. It will kill the wireless if you turn the switch off. However, turning it back on doesn’t re-enable the wireless until you re-insert the iwl3945 driver. I can script it, but still a major pain in the ass.
• Graphics: Compiz seems to work fine (though I don’t care to use it). Metacity’s compositing mode seems to work too, though it’s disappointingly slow.
• Battery: Battery life seems better than with Gutsy, provided that you’re willing to do some work. First step is to install the powertop package, run the utility, and follow it’s recommendations. Next, take a look at this guide on Thinkwiki, detailing a few more settings that can be tweaked. It still sucks that you have to do this all manually. Most of the settings are easily scriptable, and I’m sure there’s a way to automatically trigger them when you go into battery-powered mode, but I haven’t quite gotten there yet. Feels like I shouldn’t have to do this much work.
• Suspend/Resume: Seems to work. Only tried it about 5 times.
• Temperature: This is still my biggest gripe. Even with all the tweaks described above, the laptop as a whole gets considerably hotter than when running windows. Particularly the bottom side and the right side of the palm rest. While it’s better than before, it still annoys me enough that I’ll run Windows most of the time. It’s particularly bad when it’s plugged in (and some of the power saving features get turned off)
• Software: Overall, Gnome hasn’t changed much (which is a good thing IMHO). Firefox 3 seems like a huge improvement, except for the fact that FoxMarks doesn’t work yet (but I expect that to work before the temperature control does).

Progress I suppose. But less than I had hoped for. I know Lenovo sells these things with SuSE, but I don’t think the experience is much better on those models. I made a feeble attempt at running the Emperor Linux Kernel, but couldn’t get it to boot. I’m getting a little pessimistic that Linux will ever run completely fine on this machine (read: all the hardware works) during it’s useful lifetime. Oh well.