Reddit is booming, but size doesn't equate to quality of content. Lots of recycled bullshit and downright stupid shit. But it is a great news aggregator, and in some cases, a source for first hand accounts (as long as you take them with a grain of salt).
The NFL related subreddits are pretty cool, there are current and retired players, as well as people involved in the front offices of teams that do AMAs (Ask Me Anything). Fred Smoot actually became a very active member after his AMA, organizing events (tailgates etc) for the Redskins community.