Well, not all hope is lost. There are workarounds for you can pursue, but none of them are ideal.
For example, you can snag a copy of the Beta blog's site feed and run it through WP's RSS importer. This will import posts only and will only grab the 100 most recent posts (regardless of how high you set the number of items in Blogger Beta's settings). This is pretty easy, and it's better than nothing.
There are also exist hacks like this one, which is unfortunately pretty complex as it requires multiple WP installs and phpMyAdmin.
You know, now that I think about it, you could probably use Movable Type's surprisingly versatile mtimport format as an intermediary. You could set Blogger Beta to use a "faux template" that actually outputs mtimport files. You'd then save those files and use WP's Movable Type import script to pull posts and comments into WordPress. That seems like a very viable method. I'll look into that.