Note: I'm not asking how… I know that. I'm currently using Paragon Software's drivers which let you access all drive formats from all OSes (e.g. the Linux drive from OSX or the OSX drive from Win7, etc.) I'm specifically asking which is the best and why?
For instance, I want to share a data partition for documents, music and even my Dropbox account between all three OSes and I've done that between Win7 and OSX by throwing it on a NTFS partition. Just wondering now that Linux too is in the mix, if its better to set up HFS+ or linux format instead?
I'd love to share a user directory between all three, but I'm pretty sure permissions will make that impossible. However, I'm not sure.
Again, to be clear though since I'ts brought up so much below, I am not asking for compatibility with the OSes as far as access is concerned. I have Paragon's drivers for all OSes to read and write to all formats. Again, it's a question of which format is best, and why.
Best Answer
NTFS and REFS are a bad choice because Linux and Mac can't properly decode it and EXT2/EXT3/XFS are bad choices because you need custom Windows drivers for it to work.
CDFS is a bad choice because it's optimised for CDs
FAT16 and FAT32 are bad choices because they can only hold very small amounts of data ( < 4GB)
Which pretty much only leaves ExFAT (called EFS on Windows), which is readable by pretty much everyone, can hold large amounts of data and doesn't perform to badly on speed, fragmentation or corruptibility either.