I did this from a Treo 680 to a BlackBerry, and I also had my life mapped out on my Palm. The switch was easy and the best one I ever did. The most effective way to get stuff moved from Palm to BB is to use MS Outlook. Sync everything on the Palm to Outlook, then sync the BB to Outlook. Completely painless.
Remember to go the extra mile and get a BlackBerry
data plan with your new BlackBerry. It makes all the difference in your user experience.