A blog post on developer BioWare's official website
has confirmed that the next game in the popular Mass Effect series is indeed in development, but at the newly-formed BioWare Montreal, rather than BioWare's Edmonton HQ, where the previous Mass Effect games were forged (thanks VG247
The post is shy on details, but BioWare Montreal studio head Yanick Roy does confirm the developer is shifting engine technology to DICE's Battlefield 3 Frostbite 2.0 tech, and that there will be changes to the gameplay, adopting some of the features being developed by the Dragon Age team, as well as a story independent of the original trilogy -- presumably moving away from Commander Shepard's adventures:
There is really not much I can tell you about the game right now, except that it will be built with the amazing technology of Frostbite as its foundation, enhanced by many of the systems that the Dragon Age III team has already spent a lot of time building.
The other thing I can tell you is that, while it will be very respectful of the heritage built over the course of the first three games, with the original trilogy now concluded and the switch over to a new engine, we are exploring new directions, both on the gameplay and story fronts. You can still expect the pillars the franchise is known for to be fully intact though, including diverse alien races, a huge galaxy to explore, and of course rich, cinematic storytelling.
The psot further explains that the Montreal Studio was "seeded" by an assortment of BioWare Edmonton veterans to help maintain the company culture, and that the Edmonton studio will continue to support the game throughout development, including Casey Hudson staying on as Executive Producer.
No release date or platforms have been hinted at.