I'm going to go ahead and say 'very likely,' not simply because it'd be an easy cash grab for EA/BioWare and act as a lead-in for the next Mass Effect. A BioWare developer posted recently on NeoGAF asking what fans would like to see in a trilogy remaster other than the obvious 1080p/60fps. Various ideas were thrown in and while nothing was explicitly confirmed, it's long been rumored and that post solidified my suspicions.
It's a fantastic series and I highly recommend it. A remaster could be worth waiting for if it includes the DLC as there's quite a lot of it for both Mass Effect 2 and Mass Effect 3 and it's all pretty high quality. The PS3 port of the first game is also pretty awful, so if you're intending to play on a Sony console, I'd avoid it if you have the chance.
There are benefits of a next-gen collection that PC gamers don't currently have, though. For starters, I would hope that a PS4/XBO collection would include at least some of the DLC. I own most of it already and consider much of it mandatory pieces of the Mass Effect experience, but to my knowledge it must be purchased separately on both PC and consoles... and it's quite expensive at that. Additionally, there's the prospect of (officially) updated textures -- at higher resolutions on the PC, you can definitely tell the textures are being stretched, especially in ME1. Granted that the PS4/XBO versions would only go up to 1080p and I'm sure there are hi-res fan textures out there.
I heard rumors of this last year, too and I believe the devs even asked the fans about it. I am pretty sure it could be announced at E3 this year, while showing more of "ME4" or the next mass effect project.