I personally met with people from Garmin today at MacWorld (Yes, they were there) and was told that by the end of the year they would be fully supporting the Macintosh. Details after the link.

Here's their plan (or read their press release):

• Support for Macintosh uploading of data to their recently-purchased MotionBased web site through a plug-in for Safari.
• I saw a demo version of Training Center software the the Macintosh, showing data uploaded from a Forerunner 305 (which I also got to see and touch... very cool-Carol thinks it's too big).
• By the end of 2005 they will have MapSource running on the Mac.