In reply to Stone_donkey:
When I switched to LR6 from 5.x, it ran noticeably slower. I'm running an Intel Core 2Duo, 2.94GHz, with now 8Mb RAM (formerly 4Mb till quite recently). The extra RAM did make a slight difference, but not a huge amount. There was a decent thread on here at the time of the upgrade and I think the gist of it was if you have a fast processor, the upgrade did run LR faster.
The RAW pano facility which LR6 introduced is very good and works well and I think ChrisJD said he found the face recognition decent. There was also an HDR tool introduced but I don't know if it's good or not.
My personal Top Tip is to use the Lens Correction controls last of all, as that seems to slow down every subsequent command in LR!
Edit: you're right about the CC/standalone being discussed on that same thread. I went for the standalone but others preferred the PS/LR monthly licence. It was a bit of a convoluted process to buy LR outright, but it was doable then, so if it's still v.6 they're punting, I'd imagine it should still be available as such.
Edit 2:
Here's the upgrade purchase thread FYI:
http://www.ukclimbing.com/forums/t.php?t=614521&v=1#x8035087Post edited at 18:50