Yes. My MBP had Leopard, used it for 9 months, did the backup and re-installed form the DVDs. I think you have to open iTunes once on the new install, for it to generate some folders, and then you overwrite with your old folder form Time machine or any other backup. It retained all info including play counts of tracks.
Just drag back the iTunes folder form your Time Machine backup. To me this isn't a restore really as you are just copying a folder. You do not need Time Machine for this. Just copy your whole iTunes folder to the backup device/method of your choice, and copy back after installing SL. This is the best way to avoid copying back any crap from your old install and just getting your iTunes related stuff back.
rp2000