Ric Flair and WWE have agreed to terms for him to return for the next 4-6 weeks. There are several reasons why this has gone down. WWE wants to use the time period as a bridge to keep from bringing Triple H back against Randy Orton as the plan has been to headline them against each other at Summerslam in the Hell in A Cell.
Flair has been pushing hard to come back as a wrestler as financially, between alimony issues with his ex-wife Tiffany and upcoming legal-related costs regarding his son Reid, Flair realizes he's going to be hurting. His belief is that if he "can just wrestle again" he'll quickly make a ton of money to help offset those expenses, so he's completely motivated by what he can make at this point. Flair has been hoping to do some sort of return match in WWE and have their approval to return so he can take some big money offers in Japan. There has been talk of Flair wrestling at Extreme Rules but it's a Vince McMahon call and he hasn't been high on allowing that yet.
Flair has not signed a WWE deal and will still be making all of his independent and ROH appearances.