I have a Macbook running on Snow Leopard and until the last SL viewer 2 update I was running fine. I can't use the new SL Viewer at all. The lag is horrendous! And I've tried Firestorm and it's laggy too. Imprudence is the only one I can run but the graphics aren't as good. I wish they wouldn't force you to update your SL Viewer!!!! That is so incredibly annoying. It's getting to the point where logging isn't worth the trouble anymore.