Matt, when I was looking for an editing program for RAW files, the ability to do good b&w conversions was one of my criteria. I settled on Iridient Digital’s “RAW Developer”, I think it was Richard Bernabe who recomended I look at it. It gives great control over the conversion process and in my opinion the results have been good on the few I’ve done so far.
I think that having some limited proficiency in shooting b&w film with colored filters has helped bring a little more out in the digital conversions. You might want to read up a little on that stuff. The most tetious parts of the editing I’ve spent messing with the individual RGB levels in the curves panel.
RAW Developer is only for RAW files and only for Mac too. Bibble offered similar control, is supported on windows, and I THINK it could edit JPEGS too. I’m not using Photoshop for much yet though.
This is the conversion I think I’m happiest with so far:

***Damn, that’s wide, I’ll try to resize when I get home.