Yes, keeping a close eye on that. You mentioned Bits of Proof earlier, I support that effort as well. Seems to have a strong(er) code base, although don't take my word for it. Modular nodes ftw.
Bits of Proof was first, I think, but I'm not as familiar with it.
Also the Conformal guys live in the same city as I and show up at the local Bitcoin Meetups sometimes, so that's probably biasing me in their favour since I never met Grau in person.
One thing that I think would be extremely useful is if one of the teams that has done a reimplementation would start pushing code upstream to the Satoshi client, adding unit tests and documenting all the quirks they had to replicate to reduce the possible scope of an undocumented incompatibility that could cause a fork.
Maybe we could even pay for their time via a crowdfunding campaign.
When btcd presented, it sounded like they aren't quite complete yet. Maybe they have finished it in the last month. It sounds promising, I liked their architecture quite a bit. I'm not as familiar with Go, so I didn't dig into the source, but the Conformal guys definitely get it and I wish their project could get more traction.
I've also looked into Bits Of Proof, not super close, but close enough, and like that a lot too. I need to get more up to speed on JMS to really play with it more, but it has promise. That's the stack I am planning on looking at most closely going forward.