BTW- I wouldn't make this a priority, but rather a back-burner, as-you-have-time sort of project, especially since the market share is pretty darn slim compared to Windows.
However, with the current state of the econemy OSS (Linux) might make up some ground. Who Knows...
On the other hand, I almost got it running with wine on Ubuntu, so if you went that route most of the work might already be done and it might simply be a matter of tweaking some .dlls and such to get it operational using wine, which IMO would be completely excetpable. After all that is pretty much what google is doing with it's apps (google earth, picasa). Rumor has it they are working on porting Sketchup among others to Linux.
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ACAD 2012, DoubleCAD XT Pro v3, Alibre 2012 Expert, 123D