WHat is next for iraq?? Is turkey serious about an invasion? Will this mean more U.S. troops are needed??

Answer 1

What is next? Securing the border(s), as it has been for some time now. Secure them and most of the trouble within will subside... The sooner this happens the sooner we can stop propping up their government and bring our troops home.
Turkey? Hmmm, Kurdish rebels have been crossing the border into Turkey (illegally) for decades. Turkey has the right to defend itself. The Iraqi government needs to bring the Kurds into the fold and get them on the same page of music -- get them to recognize (and honor) the border. Unfortunately, these people are the third faction dividing Iraq. Until all three parties can learn to live together, there will always be a problem there.
More U.S. troops? I would venture to say that all depends on how deep into Iraq the Turks intend to go. If their intent is simply to bring into check the Kurds, then the answer is "No." Mainstream Iraq needs to get a grip on their citizens to the North.