I have a macbook pro with an SSD. Would formatting my hard drive make a difference from a speed perspective seeing as how OS X doesn't support TRIM?
there will be no speed difference if you reformat.
"across the majority of our tests, there's very little difference between the clean ssd and the one that's been used." http://www.bit-tech.net/hardware/apple/2010/07/01/mac-ssd-performance-trim-in-osx/1
"even without support for the trim command, ssd flies on mac os x" http://www.hardmac.com/news/2010/05/06/even-without-support-for-the-trim-command-ssd-flies-on-mac-os-x