Yep, noticed the same - directory PR went down for a while, followed about 3 weeks later by the toobar PR - about 3 days after that, directory PR went back to where it was before, waiting now for toolbar PR to follow - don't think it actually means alot though
If toolbar PR is erratic, I'd say directory PR is even goofier. Some sites show a high correlation between the two, while others seem unrelated. I don't think much about directory PR these days. It's too bad - I thought that the Google directory sort was much more useful than DMOZ, but it's too erratic now.
Only on G's databases there is a true PageRank score. Anywhere else, you get only aproximations (normally, you see the position in a scale from 0 to 10). Don't care about such strange variations and care your SERPs to know if your rank has truly changed (since, I guess, G's SERPs use the real PR value... or they don't?). Also, you can also use a backlink search (in any engine) to get an idea about your link popularity (wich Google formalizes with the PR equation).
Directory PR different to Toolbar PR
Normal... I'd care more if there was the same PR value in both places :P
The Directory PR is from early September. The toolbar PR is from early October (and screwed up too). Different dates, different PR calculations. The Directory is older, but I suspect much more accurate.