I really am using all of these apps. 4GB is not nearly enough to keep things snappy. CPU does a reasonable job of keeping things snappy,  except when it has to pause and swap stuff back in. I wish the new MBPs had a 16GB limit instead of 8GB. I'm worried that even if I upgrade that Snow Leopard at 64bits with use the same proportional amount of RAM that Leopard does at 32bit.

Anyone running Snow Leopard care to throw their two cents in?