That would be a good thing if Microsoft is merely shattered, and returns as a dozen newly competititive enterprises. We don't want to replace one oppressive monopoly with another.
So, how can we help keep Microsoft in the game? They do have a few options to play -- in addition to a thermonuclear patent attack.
For example, Google won't give me the Blogger backlinks (possibly related posts) I want. This is bad news; those backlinks are a key part of my manical GordonGeek-Metamind interface strategy, aka Project Xanadu. So if Google won't give 'em to me, maybe Microsoft will. 
Happily, Microsoft has several ways to play here. I'll outline just one approach, one that leverages Windows Live Writer (my all-OS favorite desktop app) and ties it to Windows Live Search, Microsoft Passport (Live ID), and Microsoft Live Spaces while facilitating an incremental Blogger to Live Spaces migration.
- Introduce the concept of domain-scoped search to Live Search, just as Google Custom Search can be used to constrain search to multiple domains.
- Write a plugin for Windows Live Writer 2009 that emulates the WordPress Possibly Related service -- call it "WLW Related". When users go to use the new function they'll be asked to enter their Windows Live ID, then to specify groups of domains to search.
- Windows Live will store this configuration on Live servers.
- Users will then be invited to optionally replicate their posts to a Microsoft Live Space which they can then create (bound to the Live ID they just created). The advantage of the Live Space will be that the backlinks created there will be dynamic.
- After initial setup future posts in WLW will always display a dynamically updated set of possibly related posts based on shared labels, and lexical analysis of the post title and body. The possibly related list will be organized by the search domains defined above. All or parts of the list URLs can be appended to the end of a blog post.
- If users opt for the optional replication of the blog posts to Spaces, they'll benefit there an optional dynamically updating "show related" set of links.
- Lastly, add an import function to Spaces that works with Google's Blog export data format. This should include dynamic updating of links so that self-referential blogspot URLs are rewritten as needed.
Give it a try Microsoft. Maybe I'll switch ...
-- footnotes --
 There aren't a lot of alternatives. Apple is busy recreating the mistakes of the 1980s. They're creating a closed software world that's going to compete with Google's (relatively) open alternative. In other words, they're Apple 1984 and Google is Microsoft 1984 (ok, so Google is nowhere near as evil as Microsoft was in those days).
Yahoo can't help either. They're waiting to be acquired. Startups are nice, but they need to figure out a Dapocalypse solution.