Blogging entices celebrities because it's an easy way to get publicity, and a way to shape their own image, said Lisa Timmons, a blogger with A Socialite's Life.
Timmons said Pam Anderson is one celebrity who uses her blog to her advantage by revealing just enough to establish an "intimacy" with fans without getting too close.
"She knows the rules and boundaries," Timmons said. "She will go on to her blog to refute things in tabloids. It's a pre-emptive way of preventing PR damage. If you have an established voice with fans, you can communicate with them."
On the other hand, Timmons said, Britney Spears has not mastered the fine art of celebrity blogging. Her attempts to "get real" with fans often result in messages that make no sense, sound like outright lies, or sometimes just make people say "ick."
"She's tried to do that, but she's just looked like someone spinning out of control," Timmons said. "She didn't know what was appropriate to post."
So, where does Barr fall on the spectrum? Did she cross a blogging boundary and now has to back pedal, or is she engaging in some savvy self-promotion?
"We'll have to see what happens," said Goodson. "But this is also the first time I've talked about Roseanne in a very long time."