Just in from the Motorola support forums is the announcement that the upgrade to 2.1 for the Motorola Backflip will take place in the third quarter of this year. With the second quarter just commencing the OTA is still not much closer, but at least the new update now has a definitive timeframe. Not the smallest timeframe albeit, but good news for Backflip owners who were told of this update a while ago.
Not much more information can be provided on a specific date other than the timeline provided. The release could be as soon as mid-summer or as late as the early fall. If the notorious hang-ups that delayed the Droid 2.1 upgrade and many others have anything to do with it, who knows if the upgrade will make it out before the fourth quarter commences.
EDIT: I was thinking in fiscal years in my original posting, but have updated the post to reflect the proper quarters based on a regular year. Thanks to the ever vigilant commenters who pointed this out and sorry to anyone who got their hopes up.