There have been a full 7+ pages of notes since I last read this yesterday so I hope this hasn't been addressed already. Just in case I tossed a tl/dr at the end.
Setting aside the stealth portion of the new stealth pool changes, calling it a "travel pool" is very misleading. Infiltration is no different (as described in the patch notes and shown in game) than any of the free movement powers. Those are not nearly on par with the true travel pool powers and it seems inappropriate that concealment should be included in the list of travel pools. While it would be nice to have another travel power--especially one that could work as half-way between Super Jump and Super Speed--Neither the movement running powers nor Infiltration come close to doing that. This is especially true now that SS has the Momentum Jump mechanic and SJ has DJ. When one claims to have a "travel power" it means one is able to get to missions in a relatively quick timeframe. If Infiltration is supposed to allow anything near that, it fails completely. If adding stealth to Athletic Run is supposed to make it worth it to use up a power choice, I really don't think many will be doing so for the purpose of travel.
That being said, I'm wondering if the idea here is to be able to have a run (not travel) power and stealth on with a reduced endurance cost compared to using both before. There's no difference at all as far as power selections. Or is the idea that now you can slot both run and jump in the run power? I'll have to experiment to see if that would turn this "movement" power into a "travel" power. Even if it would, however, I doubt it would be worth it to use slots in that way. Most of the time I doubt anyone puts more than three slots in a travel power. Slotting would likely be EndRed/Run/Jump (1 or 2 each, depending on how many slots you want to devote to it) since the Defense buff would be meaningless. I doubt many people would want to 6 slot a travel power, especially when it still wouldn't let them come close to keeping up with others who have their travel powers one or two slotted.
Lastly, as to the defense portion of Infiltration: neither Combat Jumping nor Hover lose their defense buff while in combat. Infiltration has no immob or KB mitigation so why does it lose the defense when the others doesn't lose anything? It also suffers from the suppression that happens during combat so as far as speed/jump, it's no better than CJ. All in all, it makes no sense to spend a power choice on Infiltration when you can get Athletic (etc) Run for free. Again, the exception would be for endurance cost limits. I can foresee some arguing that since the defense comes from the stealth and the stealth is meaningless once the foe is aware of you, so logically the defense must be lost. If they were to set mechanics to be logical this game would cease to exist, so that argument doesn't hold water. Besides, the defense should be coming from the maneuverability just like it does in the case of CJ.
Coyote
TL/DR: Infiltration should keep its +Def in combat, just like CJ does and Concealment doesn't deserve to be called a "Travel Pool".