Edit: The Houston radio station was incorrect with their report. Wilfork is signing with the Texans.
Yesterday we noted that three AFC teams, other than the Patriots, were vying for Vince Wilfork's services and all three had substantial offers on the table. Those teams were the Texans, Colts, and Ravens.
According to Houston's Sports Radio 610, the Texans are no longer in consideration. Wilfork was spending time with the Texans on Sunday and Monday, but no papers were signed.
Houston was considered a front runner due to Wilfork's familiarity with the coaches and scheme. Head coach Bill O'Brien, defensive coordinator Romeo Crennel, offensive coordinator George Godsey, and linebackers coach Mike Vrabel have all spent time on the Patriots in the past, alongside Wilfork, and defensive assistant Anthony Pleasant was a part of New England the year prior to drafting the defensive tackle.
This means that Vince is deciding between the Patriots, Colts, and Ravens, arguably the three teams in the AFC that give him the best chance of making it make to a Super Bowl. The Patriots are his home, while the Colts have made an aggressive push to sign Wilfork. The Ravens are a sleeper pick, but they offer stability that Wilfork appreciates.
Edit: It looks like Wilfork isn't expected to visit the Colts, either, per ESPN's Mike Wells.