White House press secretary Robert Gibbs has another podium -- Twitter.

President Barack Obama's spokesman joined the microblogging service on Saturday and has already attracted nearly 18,000 followers.

"Learning about 'the twitter' -- easing into this with first tweet -- any tips?" read his first message.

Gibbs followed it up the next day with: "wow -- in a less than 30 hours almost 17K of you are following -- amazing -- watch out Kim Kardashian! Thanks to all for the smart tips!"

Gibbs has a long way to go, however, before he keeps up with reality TV star Kardashian, whose Twitter account, @kimkardashian, has nearly three million followers.

He also has a long way to go to catch his boss, whose @barackobama account has more than 3.2 million followers although the president has acknowledged he doesn't send his own "tweets."

The Christian Science Monitor notes that Gibbs has already faced some tough criticism from the more experienced Twitter community.

"Watch out," Jimmy Orr writes. "Because plenty of people went straight for the jugular."

fleckman: Shouldn't Gibbs new twitter acct be @PressSUK instead of @PressSec

And:

rosecityken: @PressSec say more here than you do in press conferences, you will cut out like 250 "uhhhh's" in like 5 mins time.

And:

1stCavTommy: @PressSec Yes, explain to me again how Iraq will be one of Obama's great successes. Then resign.

Orr notes. "Others seemed genuinely happy he was online.

patricdhawaan: @PressSec Keep up the good work. Disregard the nut-jobs. Moderate Republicans like me see through the Fox news filter.

Gibbs is already using his Twitter account to defend John O. Brennan, Assistant to the President and Deputy National Security Adviser for Homeland Security and Counterterrorism, who is facing calls to resign partly based on statements he made this weekend regarding alleged recidivism at Guantanamo.

"People sometimes use that figure, 20 percent, say 'Oh my goodness, one out of five detainees returned to some type of extremist activity,'" Brennan said, during a speech at NYU Law School on Saturday. "You know, the American penal system, the recidivism rate is up to something about 50 percent or so, as far as return to crime. Twenty percent isn't that bad."

Brennan added, "Many of these detainees have returned, have engaged not just extremism, but terrorist attacks. It is something that we have to look at very carefully."

Gibbs' Tweet links to a Politico blog by Glenn Thrush, which reports that "former Secretary of State Condoleezza Rice made a very similar argument during an AP interview in 2005. And she, like, Brennan likened the rates of recidivism among enemy combatants to that of American criminals."

"Condi Rice sounded a lot like Brennan when talking about GTMO in '05," Brennan Tweeted (and Gibbs reTweeted. "But nobody called for her firing."

Critics have complained that the recidivism figures are wrong.

A Seton Hall Law School report argued, "Just as the Government's claims that the Guantánamo detainees were picked up on the battlefield, fighting American forces, trying to kill American forces, do not comport with the Department of Defense's own data, neither do its claims that former detainees have returned to the fight. The Department of Defense has publicly insisted that just short of thirty former Guantánamo detainees have returned to the battlefield, where they have been re-captured or killed, but to date the Department has described at most fifteen (15) possible recidivists, and has identified only seven (7) of these individuals by name."