I didn't catch this when it happened, but Seneca returned two punts last Sunday in the game against the Bills after Burleson went down with injury. Now word out of Seattle is that he may START at WR this week! He must be flashing some amazing stuff in practice to be able to jump immediately into the starting role.

From rotoworld.com:

The Tacoma News Tribune believes there's a "good chance" that Seneca Wallace will step in as the Seahawks' starting split end, replacing Nate Burleson.
Coach Mike Holmgren also wants to add a veteran. It's unlikely that Wallace has wide receiver eligibility in any fantasy leagues, and he'd be a poor play over a QB. Holmgren may name a starter by the end of the week, but it's a good bet that whoever it is will rotate with Logan Payne and Jordan Kent.
Source: Seahawks Insider Blog