HOT OFF THE PRESS
Garmin announce "HOME PORT" PC Passage planning and waypoint management tool.
https://buy.garmin.com/shop/shop.do?pID=64242
This nicely solves the problem of MapSource/Bluechart being discontinued. It appears "home port" will work with both pre-programmed SD cards, and SD cards with back up copies of pre-loaded charts for customers who purchase models with built in charts.
Thanks, Froggie. I missed this post until now, but did write an entry on HomePort:
https://www.panbo.com/archives/2009/10/garmin_homeport_finally_the_planner.html