I saw played a reasonable amount of Outland at PAX Prime yesterday, and have perhaps a slightly better grasp of what's going on here than some of the articles floating around seem to. 
In some respects, Outland wears its influences on its sleeve. The  polarity mechanic not only works like, but looks almost identical to the way it did in Ikaruga. As you platform through the game, there are often emitters that will fire bullets of varying color and geometric patterns, which you must match the color of to avoid injury. Unlike in Ikaruga, getting hit means losing health, not instant death. 
There are, however, a lot of complications thrown your way over the basic formula. While avoiding bullets of the wrong color, you are also forced to fight various enemies, such as spiders. Most of the time, these enemies will have a polarity themselves, and rather than simply do half-damage if you are of like polarity to them, Outland takes it further and renders your attacks useless — you absolutely must be of the opposite polarity to do damage to these enemies. In addition, there are a lot of puzzle- or action-based mechanics in the world of Outland that are based on your polarity: moving platforms won't move, some stationary platforms will simply disappear, and ornate patterns of light won't illuminate unless you are of the correct alignment. 
 
Visually as well, there are influences there. I'm reminded strongly of Shadow of the Colossus in terms of environment and character design, while the trails of light are reminiscent of Tron, or perhaps even some of the more ornate patterns in Twilight Princess. 
 
I asked the developer who was demoing the game whether there would be co-op of some kind coming. He pulled a "haven't announced anything," which to me meant yes.