GMA: Can Celebs Rehab Their Careers?

This morning on Good Morning America they talked about celebrities who are making appearances on television shows in an effort to put their troubled pasts behind them. 

For example, Lindsay Lohan made an appearance on Ugly Betty and Britney Spears showed up on How I Met Your Mother. 

They also talked about how it can backfire (the example they chose was American Idol judge, Paula Abdul, for her reality show “Hey Paula.”).

What do you think?  Do these appearances on sitcoms help repair celebrity images?