Are the tweets from celebrities genuine? Are they twittering or do they have assistants doing that?
—Dr. Joshua, via Twitter
Hey, let's make this a quiz. Because this is entertainment journalism, that’s why, and if it’s not in countdown form, it needs to be a quiz. Here are some names: Hayden Panettiere, Leonard Nimoy, Greg Grunberg, Shaq, Henry Rollins, Britney Spears, Tina Fey, Demi and Ashton, and the latest Dr. Who, David Tennant.
Some of those people really twitter, some do not but have impostors who would have you believe otherwise, and still others fall somewhere in between.
Take your best guesses and keep reading. (Here's a hint: If you don't know by now that Heroes' Grunberg really twitters, and a lot, you are a corpse. Now, seriously, continue.)