http://indiegames.com/blog/ is the main one for me. They're very good at finding news and rarely miss anything that's going on in the indie games scene. TIGSource is alright but is definitely more selective in what gets onto the front page, so you'll miss a lot of good stuff if that's all you check.
i believe tigsource is the best source for information really. every other blog ive been to is just ripping off tigsource- at least i havent found anything anywhere else that wasnt already mentioned on tigsources. i guess its good to have one place where you find all the information you need instead of having it all scattered around on different pages.
Another useful thing you can do is sign up for Twitter and connect with other game developers. A lot of information gets spread around by retweets and community movements like #screenshotsaturday (http://www.screenshotsaturday.com/ )
Twitter is okay sometimes, but most developers spam and retweet way tooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo much.
I don't so much try to get information on specific new games. Instead, I try to follow the general "scent in the air" to make educated guesses about what form games will take in the immediate and distant future. In fact, it would be interesting to run a computer model that would take various factors in both the professional and amateur game environments and utilize them to produce a well-informed guesstimate about the themes and patterns of up-coming releases. It will be a while before I can try this, as I do not plan to design such a system yet, so I must settle for manual observation for now. For this reason, I enjoy the atmosphere of ResearchGate.