Hi there, I'd say that's a pretty good deal, keeping a few things in mind. If the computer meets your needs, I wouldn't worry too much about the absence of Snow Leopard. Look specifically at the processor speed, memory space and RAM, and if you think the machine is capable enough for your application (it's no screaming new powermac, obviously, but isn't a weakling either) then I would say take advantage. It's an intel machine which is of course a positive. I would make sure to examine the machine closely to make sure it is in good physical shape, and if you do end up getting it test the battery life immediately to make sure it's up to your expectations. As far as OS, I have both an iMac running Leopard and a new MBP running Snow Leopard...to be honest, you will likely be perfectly happy running Leopard as it is an excellent OS and the improvements in SL are generally small, streamlining features. That said, if you really want the latest and greatest, I would upgrade right away before you make too many changes and installs since some cleanup will be required before upgrading if you do. Upgrading is only $29 (hopefully having a refurb won't change, that but it may-someone else may know more about that than I), and if you decide to do it I would follow this guide
http://lifehacker.com/5348150/how-to-upgrade-from-leopard-to-snow-leopard or one like it. One more thing to keep in mind is the warranty that the refurb shop offers-make sure they offer at least some coverage in case you uncover a hitch in their work (very unlikely, but still a good idea to have some reassurance). Also, try to haggle a bit ($725, $750?) you never know, and it can't hurt to try. Best of luck!
