Avid announced that 10 is the last version to support a lot of present/older hardware, which includes 002, 003, blue interfaces(96io and 192io), HD cards.....) 11 will be a ground up rebuild of the software and will be 64 bit, but some stuff had to go bye bye in the name of the future.
Back to the question on 10 with the 003, as with ANY update, do it smart. Get another hard drive and clone your present system drive. Then swap the old drive with the clone, and do all your updates on the cloned drive. That way, if anything goes sour, you can revert to the old drive and get work done(IOW, always have a backup plan)
Acronis True Image(or similar) is a MUST HAVE for every DAW user(okay, down off the soap box
)