In doing some research regarding ColorThink 2.2 I came across quite a few postings that said it would grind to an absolute halt if you tried to analyze the gamut of a full resolution photograph (a lot of folks were downrezing their files before opening them in ColorThink). I just purchased it yesterday and got my key today so of what's the first thing I do (the plate is hot, don't touch it... of course I touched the plate)... anyhow, looks like they may have improved the performance in the beta as I opened a full resolution 8 bit file from a Nikon D700 and it opened instantly, no waiting at all. Just thought I'd put that out there as an FYI if anyone is interested. Of course I never used previous versions so I have no frame of reference. Very useful tool (quite educational as well)! I'm not sure why I didn't buy it a long time ago.
Cheers, Joe