In Mass Effect two, lots of things will be transfered over. Your decision to save or kill Wrex, who you chose to save on Virmire between Kaidan and Ashley, how you treated Conrad Verner, if you saved or killed the Rachni Queen, etc. Decisions like these will be transferred over with any completed game save in Mass Effect one. Rumors are that you can choose which one you wish to start on and what decisons you wish to select as your "determining factors" in the new game. So far as I know, the only thing that WON'T be transferred will be your level, armor and weapons, and any acquired skills and talents.