So, one of the best local websites about local developments, existing, new, and under construction, is the Architectural Boston forum. There, you can read all about Boston architecture and design. I read it, religiously. (There’s also good coverage of architecture and design throughout New England, the US, and world.)
One of the regular posters to the forum, Andrew Lynch, has created an awesome map of all the local developments.
You can see each new development, plus follow it back to the Architectural Boston forum, to see what everyone thinks.
If you have an opinion on a project, or know something interesting about it, I strongly suggest creating your own forum account and getting involved!