superficial observation might suggest that blog-search & -indexing is a problem solved long time ago - after all we have specialised blog search-engines like Technorati, sphere and Icerocket. however, Technorati - blog-search pioneer and defacto market-leader - is afflicted by repeated technical problems (like randomly “forgetting” to index blogs for weeks - just google for wordpress + technorati + troubles) and performance-issues (after all, a ping after updating your blog should lead to almost immediately updated indizes, and not lagging several hours behind). another problem Technorati shares with all its competitors is the uphill combat against spam-blogs (aka ’splogs’) & replica-blogs. [disclaimer: in no way this should be a rant against Technorati - I'm using the service almost daily and don't see any real alternative at the moment]
you might suppose Google should’nt really have a problem to establish their very own kick ass blog-index, but like their online RSS-reader, which has only gained attention after its recent major upgrade, blogsearch.google.com has been living quite below the blogosphere’s radar. according to the screenshot (see below) blogger Andy Boyd has posted today, this might be subject to change in the very near future: in what might be a local beta-rollout, Andy seems to have received results from blogsearch mixed within the general results from google.com:

TechCrunch points out that this might be a “believable scenario because Google recently added blog search to Google News last month and to Google Alerts four days later”. indeed, Google would be the first mainstream search-engine to specifically incorporate blog-posts into their search-results. a great boost for the blogosphere in general, and smaller bloggers - holding a lower page-rank - in particular could be anticipated. so let’s sit back and see what’s coming (soon, hopefully) on google.com…:)
update: here’s what Google Blogscoped has to say about this:
Also, I wonder how Google wants to decide on quality for these blog links – surely they can’t allow any recently updated spam blog to inhibit this spot, but for very fresh posts it might also be hard to rank this in terms of backlinks… unless they manage to count blog-post backlinks in near real-time.