Twitter desktop client Seesmic became one of the first - indeed, the first that I know of - Twitter desktop clients to integrate the microblogging service's new Lists feature.

TechCrunch's Leena Rao reports:

Today, Seesmic is announcing the availability of Lists on its desktop client, Seesmic Desktop.

The new, downloadable version of Seesmic Desktop will display your Twitter lists in the left sidebar from any Twitter account you have (Seesmic lets you use one client for multiple accounts). The new feature also lets you add any Twitter user to any user list from any of your account.

Twitter began rolling out its Lists feature last week. One limitation of Seesmic's Lists function is that you have to create your lists from Twitter's web site. Supposedly Seesmic will eliminate that extra step in the next few weeks, allowing users to make lists from its desktop client.

(Rao also reports that Seesmic desktop has reached the 3 million download mark, though Seesmic itself still has the figure at 2 million desktop downloads on its web site. Too busy creating to update the number, I guess.)

Seesmic competitor and predecessor TweetDeck is expected to add Lists functionality soon, according to Rao.