2. The Falcon
Sam Wilson is a long time crime fighting partner of Captain America who has the ability to fly using a high-tech flight harness with wings. He has the ability to telepathically communicate with birds, and can even see through their eyes. He first appeared in Captain America comics in 1969 as the first African-American superhero to appear in mainstream comics. He and Captain America operated as a crime fighting team in New York through most of the 70s. The Falcon also became an Avenger during this period. Captain America and The Falcon continue to work together frequently in comics as partners and as Avengers.
Why should we expect him? The Falcon is set to appear in Captain America: The Winter Soldier played by Anthony Mackie. The picture above is concept art for his appearance in The Winter Soldier. It is unclear at this stage whether Mackie will get to reprise the role in The Avengers 2. Iron Mans partner War Machine did not appear in The Avengers, but unlike War Machine, The Falcons powers are very different to his partners powers. The Falcon is also set to appear in the Avengers Assemble animated television series. This series is a replacement for the previous animated series, with a new line up and character designs that are more consistent with the MCU. This may be an indication that The Falcon will also join the Avengers in the MCU.