We already know that top Twitter topics come and go however Twends show just how popular a subject is on the social networking site and Britney Spears and her new album Femme Fatale is proving to be a huge Twend.

Already the Femme Fatale Twend has been running for more than seven days putting itin the top ten of all Twends recorded since the service began last year.

While Britney is moving on up the chart the longest ever Twend recorded so far has been that of the film “Inception” which was a Twend for more than 39 days while the “World Cup” as a subject remains at number two as a Twend of 21 days.

“Twend.it” was started by US students Nick DiFilippo and Tim Kelleher in May 2010 to show a historic view of Twitter trends and while Lady Gaga and Justin Bieber may be big on the Twitter charts it is Britney who is topping the charts in the Twends being the only music star to feature in the top ten.

Britney tweeted to fans: “Can´t believe Femme Fatale has been trending for six days. You guys are my motivation every single day. I love you all!!”

The importance of Twends is seen as cultural by one of its founders Nick DiFilippo who said that social networking sites were a great way for artists to reach their fans more directly.

“They are finding a way to connect with their fan base,” he said.