I can't seem to get Huffyuv as an option to export my video in Premiere CS5, it worked in CS4 so I'm not sure if you have to install in differently for CS5.
Lagarith is still an option, though I personally have preferred Huffyuv to Lagarith.
Also curious on others' opinions on using Lagarith, or if there are different codecs for lossless video out now?
I think you're limited to x64 codecs.
As for new codecs, there is one that compresses almost as much as Lagarith, but is much faster than Huffyuv. It's UTVideo and it does come both in x86 and x64 flavour.