Most of the above posts seem to undervalue Legwand. He is a solid two-way player with over 1000 games of NHL experience and over 600 points (former #2 overall pick). And, he can play in all situations (led the Sens in PP goals last year). At worst he provides veteran mentorship for our two young centers for a year. And, with only one year left on his contract if he becomes expendable he can be dealt at the deadline.
I've watched the guy play for years down here and unless his skills have really fallen off over the past year, he will be in the lineup this year for the Sabres (probably 4th line due to CodyMac's health concerns).