After the WordPress upgrade, I was also able to get my del.icio.us bookmarks to post using their Daily Blog Posting Thingy. (Hey, I didn't name it.) You can find it under the setting menu in your del.icio.us account (http://del.icio.us/settings/$username/daily).
That's all good stuff, but now I'm having problems with my WordPress RSS feed. Looks like it might have something to do with the .htaccess mod_rewrite stuff.
Any ideas? Bueller? Bueller?
Update: Googled a bit and found this. Still haven't fixed it, but I think I'm on the right track.
Update 2: FeedBurner receives my pings and then posts the latest entry, but accessing the feed directly doesn't work. Should I care? I do, only because my del.icio.us links will appear twice in the feed, once as a post and the second as part of the FeedBurner "Link Integration."