I’m about to acquire a Mac shortly with a shed load of hardware (all for an absolute steal too 
) from a musician who has to make room for offspring (seriously… What kind of pioritisation logic is that?).
Anyhow, a couple of questions as I know nothing of macs…
Will my current crop of PC VSTs work ok on the mac as well?
Essentially, can I transfer my existing work, instruments and samples to a Mac platform easily?
Windows VST plug-ins will not work on Mac. Some of them will work with special tricks/hacks, but you cannot rely on this. You will need to get a version of the same plug-in that is compiled especially for Mac - either as VST or AU - to make sure that it works correctly. A lot of commercial plug-ins offer both Windows and Mac versions, but with the freeware/shareware scene it’s more of a problem.
If it’s a native Renoise song that only uses Renoise instruments, then you should have no problems. If it’s a song that uses a lot of plug-ins, then see the above info.
Damn.
I’ll probably be better building a new PC to use with all my existing stuff. It will be much cheaper than buying Mac versions of my VSTs.
Oh well, I always knew Macs were trouble 
Any reputable company that sells plug-ins will give you access to both the Windows and Mac version of the software for no extra charge, so hopefully you should not have to re-purchase anything.