Migrating to WordPress.com :: Is it feasible?

I’m thinking of migrating a few of my blogs to WordPress.com. Is it doable?

The blogs I’m thinking of moving over here are infOpinions? and Marcomblog.

Now, we’re talking about hundreds, if not thousands, of posts and all the associated images and multimedia files.

I wonder if this is possible and where the instructions might be. Anyone done such a migration?

I’m aware of the Manage -> Import function, but not sure if that can work for all of those posts.  There is, I believe, a 10mb limit to importing xml files.  So, is there a way to transfer a database?