I recently made the day to day switch from Linux to Mac OSX running Lion. For the most part this transition has been painless, although there is just enough different for a Linux user to scratch his head and say "huh, Apple what were you thinking?". Now for completeness and full disclosure, I made the change from MS Windows to Linux over 6 years ago and only use Windows when I have to and only via VMWare Workstation (http://www.vmware.com), so these posts are not about how to do things from a Windows world because I have not lived in that world for a very long time and I will never go back. It is like once you drive a German car, it is really hard to drive anything else.
I hope you will find these random posts helpful if you are migrating from Linux to Mac OSX.