I am in the exact same boat.
When I started my site <snip></snip> I submitted it directly to Yahoo and Bing at the time, as well as google. This was a few months back. I didn’t bother publishing the blog live until I had a half dozen or so content posts lined up, so that shouldn’t have been an issue.
Google indexed me right away, and these days I am seeing a new post indexed by Google within a minute or two of going live. This I am extremely pleased with, and Google is starting to be a very good source of traffic.
Bing/Yahoo, nothing, nadda, bumpkiss.
I submitted using Bing WebMaster tools. I have a sitemap. I have 100% generated, non duplicated content, I use an established CMS. Finally, I am hosting on one of the servers of my primary site, and that other site is indexed just fine.
Using Yahoo Site explorer, I see 3 pages <snip></snip>. Using Bing, nothing. This is for a site that has been live for months and has over a hundred pages now and has over 100 sites linking in.
I am at a bit of a loss at this point. I know Bing/Yahoo represent a tiny fraction of search traffic, but just throwing that traffic away seems to be stupid, especially considering how much traffic I get from yahoo answers.
That one really got me, my site is linked by yahoo answers, but yahoo doesn’t index that!
I hate to say it, but I think Bing is seriously broken, at least for new sites. In search, you see tons of similar comments and no answers from Microsoft.