Update 12/29/10: Nope, either the rumor was false or Samsung/Sprint decided to delay the update once again:
Epic 4G users, remember the Froyo update (DK28) that we thought was final but turned out to be nothing but a leaked test build? Shortly after the leak, Sprint released a statement discouraging the download and reaffirming the official latest supported build was Android 2.1 with Sprint's software version DI18.
The wait resumed, but not for long, as an official-looking photo of what looks like some sort of a memo in Sprint's internal customer support system, showed up over at Phone Arena. The update, dubbed DL11 (corresponding to Android version 2.2.1), is promised for the day after Christmas - December 26th, 2010. According to the memo, it will be released as an OTA (over-the-air), applied directly on top of DI18 (with patches for older versions DI07 and DG27 coming later).
If this information is indeed legitimate, Epic 4G will likely still manage to be the first Galaxy S series device in the U.S. to get upgraded to Froyo. I am experiencing both sad and happy feelings at the same time. Let's hope that it's true and that this time, Samsung won't pull it right back a day after, like it's been doing recently. <INSERT FROWN HERE>
Source: Phone Arena, thanks Cary