Its algorithm seems to work really well for rapid consumption of buzz within a particular network that you can tap into by following people. It is one of the few cases where I like the fact that I occasionally get out-of-network Tweets in my timeline because it usually exposes me to something really interesting posted by someone outside of my direct field. I'd never want to use Twitter for comprehensive reviews of some topic, reliable back-and-forth discussion, etc. but it's just fantastic for gossip and trends.
The tables here are even starting to turn–so many people are on Science Twitter that it feels like I find as many new and relevant papers on Twitter as I do in my tailored email notifications and RSS feeds. Twitter is also always a day or two ahead, and the papers usually come with the backstory and context in plain English. I hate to say that the Twitter thread from the paper author is often more informative (at least, per unit of time that it takes to consume) than the content of the paper itself.