It all depends on who you follow, as Veronica says. There's a lot of noise on Twitter, but some interesting stuff too. I enjoy following bike racers like Lance, Levi, Dave Zabriskie, Robbie McEwen, George Hincapie etc. I also enjoy following my friends, other Boston Terrier folks (who post some really cute photos), some weather and news outlets, green/eco sites, and some folks who watch the same TV shows I do and comment on those.
I can pop in when I want and ignore it most of the time. I use it only from my computer, not my cell phone. For me, I think it's less time-intensive than Facebook would be, which is why I haven't signed up for FB yet.
Emily
2011 Jamis Dakar XC "Toto" - Selle Italia Ldy Gel Flow
2007 Trek Pilot 5.0 WSD "Gloria" - Selle Italia Diva Gel Flow
2004 Bike Friday Petite Pocket Crusoe - Selle Italia Diva Gel Flow