It's the Marvel's Agents Of S.H.I.E.L.D. logo with the Captain America 2 shield behind it.
Ming-Na Wen added:
#AgentsofSHIELD has #CaptainAmerica's shield in background in #ABC ad! So epic! New ep this tues, March 4th, 8pm!
It's previously been said that Captain America 2 will help fill some gaps with Marvel's Agents Of S.H.I.E.L.D.
What exactly that means is anybody's guess, but tune in to ABC For Marvel's Agents of S.H.I.E.L.D. and in theaters for Captain America 2 on April 4th to find out.
Updated: with video below.