Ubuntu Networking :: Sudden Loss Of Wireless Connection

For most of today I had my internet connection dropping out on me intermittently. I assumed it was a provider issue, as it has been unreliable in the past. After it dropped out for good, and I could not print through network, I realised it was not a provider issue. All the other computers in the house were connected, including another ubuntu box. Only the MacBook Pro 5,5 was not able to connect. The network manager indicated I was connected to the network, throughout the whole time.

A number of restarts with the kernel I normally use (2.6.31-19) including one in recovery mode, yielded no change, but a restart with the 2.6.31-20 kernel resulted in connectivity. Finally, perhaps by chance, wireless started to work again on the 2.6.31-19 kernel, after I once booted into the Mac OS, and then back into Karmic. How I might go about diagnosing, obviously in hindsight, what happened? I suppose I should look in the log files, but I have no idea where exactly, and what to look for.