The Season 6 finale of "The Big Bang Theory" sent Leonard on an expedition to the North Sea. The Season 7 finale has sent Sheldon out of Pasadena on an expedition to discover himself. There is no doubt that Sheldon will return when CBS's hugely popular comedy series returns for Season 8. There is likely to be some change in Sheldon when he comes back. The one change that is confirmed is that he will appear on Mondays, and not Thursdays.

This change of telecast date, however, is not permanent, but a brief one. "The Big Bang Theory" Season 8 will premiere on Monday this fall [sometime in September] due to Thursday night NFL telecasts. It is scheduled to move back to Thursdays on October 30, 2011.

In March, 2014, CBS renewed "The Big Bang Theory" for three seasons, which showed the show's immense popularity and CBS's huge commitment, as a result of that.

"This multiyear deal further strengthens our network's position for future seasons and marks another chapter in the great partnership CBS enjoys with Warner Bros. Television for delivering audiences the best in comedy," said Nina Tassler, chairman of CBS Entertainment, as quoted by Zap2it. "We're proud to work with and showcase the incredible talents of [executive producers] Chuck Lorre, Steve Molaro and this amazing cast every week."

In Season 7 of "The Big Bang Theory," Penny and Leonard got engaged, Raj found an understanding girl in Emily and they kissed and had sex, Howard and Bernadette relationship continued to be their kind of normal. Stuart saved this couple from a possible breakdown by taking-up the difficult job of taking care of Howard's screaming mother. Stuart and Howard's mother hit-it off like close friends.

Sheldon and Amy's relationship took baby steps and there was a noticeable change in their comfort level in Seaosn 7. In one of the much talked about episodes, Sheldon kissed Amy on her lips and it seemed like he enjoyed it. It will be interesting to see how the dynamic of Sheldon and Amy's relationship change after Sheldon comes back from his discovering-self expedition.

One cannot wait to see what kind of changed behaviour Sheldon will be displaying, and what he was up to.