Basically without TRIM over a period of time a SSD becomes soo slow it is unusable (TRIM removes garbage, lots of garbage = slow). That is unless the SSD has inbuilt garbage collection. Currently the future of TRIM in MBPs is a will happen but not until Lion but even then what SSDs? If you are looking to get a SSD, just get a Vertex 3 or OWC 6G SSD.
You won't regret it.