There's twouble in the Twitterverse!

After famously beating CNN to 1 million followers last April, Ashton Kutcher has been the undisputed king of Twitter, gaining more followers than anyone else on the micro-blogging site. But are his days as Twitter's most popular user numbered?

Britney Spears is slowly closing in on Kutcher – and the gap between their number of followers gets smaller every day. (At the time of this posting, Kutcher had 4,890,797 followers; Spears had 4,878,516). While Kutcher is the only person who Tweets on his account (several times each day), Spears only sporadically posts on her Twitter account, along with her manager Adam Leber.

Now, the big question remains: If Spears does beat Kutcher, will she ding-dong ditch his doorstep the way Kutcher promised to do to CNN honcho Ted Turner?