Twitter and TweetDeck are keeping tight-lipped about a fresh report from CNN that the social networking site has acquired one of the most popular Twitter clients.

We’ve been through these reports before. Three weeks ago, TechCrunch reported that the acquisition was a done deal that would be announced within the week. Before that, the Wall Street Journal reported in March that the two companies were in talks for a $50 million deal.

The deal has yet to be officially announced, and Twitter’s PR team sent out the following message, shortly after the CNN report ran:

For all those who might be curious, we continue to not comment on rumors.Tue May 24 01:31:28 via webTwitter Comms

TweetDeck was also said to be in talks with UberMedia — a company that has several Twitter clients, including UberSocial.

On Monday, UberMedia launched another Twitter client in partnership with actor Ashton Kutcher.

If Twitter does acquire TweetDeck, many users worry that the application — which allows users to monitor several social media Web sites simultaneously — will either be killed or changed . Twitter has made it clear that it wants to shrink the ecosystem of third-party Twitter applications.

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Ashton Kutcher and UberMedia launch a Twitter app

Report: Twitter buys TweetDeck

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