Eight-year BBDO New York vet Greg Hahn, who’s worked on efforts for accounts including AT&T, FedEx, GE, HBO, has ascended to the big chair and taken on the role of chief creative officer at the agency. We’ve been told the position has been vacant, but as a result, Hahn will be working closer with his old Fallon colleague David Lubars, his director boss who of course serves as chairman/CCO of BBDO North America. In a statement, Lubars sings Hahn’s praises, saying, ““Greg is a brilliant and creative leader. Also a humble, great soul. He’s someone who has been helping to lead his clients forward for as long as I have known him/ Greg was behind the award-winning ‘HBO Voyeur’ project which took home a record-setting ten Lions at Cannes. He’s also pioneered new ideas in mobile and social. As Chief Creative Officer, Greg will now be able to bring this thinking to a wider array of clients – it’s how we can help them be that much more relevant to their customers and stay ahead of the game.”