For this year his deal is still 2.3 mill but a 5.1 cap hit. But in the following years were looking at 5.4-ish in cap hit.
Very reasonable in my opinion.
"Updating a previous item, the Bills signed C Eric Wood to a four-year, $25.4 million extension through the 2017 season.
The deal includes a $9 million signing bonus. Wood's new deal averages $5.45 million annually, which slots him in as the fifth-highest paid center just ahead of the Giants' David Baas. The former first-round pick graded out as Pro Football Focus' No. 11 center last season. He'll make $2.3 million in 2013. Aug 31 - 5:19 PM"
http://www.rotoworld.com/player/nfl/5305/eric-wood