svn annotate is unfortunately a bit slow (tried it on src/program.c, takes 35 sec vs 7 sec with cvs)
that is 5 times as much. checkouts will be slow (i saw someone complaining about it not being done after 24 hours (but maybe he was checking out all versions)
Annotate behaviour will probably not affect checkout behaviour, but we will probably notice many operations taking vastly different order of magnitude time to complete. I expect many (particularly tag/branch related) operations will speed up significantly instead.
I would not expect checkout to be one of the operations that take much more time than with cvs (based mostly on the subversion team's goals).