I recommend it. Dean Esmay helped me do it. Best thing I ever did. Once had done it, I wrote a DT (drunken treatise) on how to move old Blogger/Blog*Spot posts from Blogger to Movable Type.
If you are having problems in that area, and have found this site because of them, look here. Otherwise, read on.
[Update (6/26): Apparently, since I wrote the aforementioned DT, Blogger has changed its interface, and my instructions no longer work. Specifically, I have been told that the date format MT wants to read is no longer offered by Blogger. (Can you say Google conspiracy? I knew that you could.) I don't know how to fix this, and I am on to greater things, so I can't help you any further. But good luck!]