Is it possible to import a wordpress backup from a single site in to a multi-site configuration?

Question

I have a local development server with WordPress installed (my desktop Linux Mint 12 box). I'd like to use multi-site WordPress to manage my different client projects through one install, but I have a couple of important questions before I commit to this set-up.

1) Is it possible to import a database backup (created from the Admin Panel's backup tool) from a single WP site into a multi-site child site?

2) Vice versa -- Is it possible to export a multi-site child site's database and import it in to a single site? (for migrating from my dev box to the live server!)

3) Are there any other 'obvious' problems that I should worry about when using this kind of set-up for localhost development?

Community question: What method(s) do any other developers out there use for managing multiple WordPress projects?

All advice / help / guidance greatly appreciated!