Considering that a tweet is only 100-something characters, your use is essentially equivalent to following an RSS-like feed for a news site. The only difference is that the newsmaker can be anybody and you don't get to read a full version of the news article. Right?
(Personally getting news off Twitter isn't a reason I use it.)
If you follow a feed that basically just outputs an RSS-esque feed of titles and links, then yes, it's just an interface for RSS.
You can also follow people and/or organisations that editorialise in their tweets. For example, if you want tech news from BBC, you could get a basic RSS feed, or you could look to someone like Rory Cellan-Jones and could follow his work account (@BBCRoryCJ) which is basically just BBC stuff, but not the same info you would get from an RSS feed with some extras added in, or his personal account (@ruskin147) where you get more personal thoughts/opinions etc.
And another option, getting news from your friends - so, in theory, that can provide you with interesting content from random different sources that fit your interests, which an RSS feed won't do. So it's kinda like what a sub-reddit is to the reddit frontpage, except purely personalised on who you want to follow.
The other commenters said most of it already but here's what I do. I follow multiple headline accounts (BBC, Sky, Al Jazeera, Reuters etc), those tweets usually have a headline and a link to the article if I want to read the rest.
I follow around 100 accounts at any one time, and frequently prune the list so it doesn't get to busy or full of stuff I'm no longer interested in.
I also follow specific journalists, politicians, science and tech people who also often link to things they're reading which are useful background for what's going on.
By far the most useful thing is creating custom columns in tweetdeck for search terms. Think of it like this: rather than subscribing to an RSS feed for a site and hoping they post stuff I'm interested in, it's more like automatically generating a news feed on any subject you're interested in. I have a bunch of saved searches on all kinds of subjects, some of them may only get one or two tweets a week, but it keeps me up to date.
Another benefit to using searches is that it's a good way to discover people who are consistently tweeting interesting stuff so you can follow them. Without the search I would never have heard of or thought of following some of the people I do.
Yes. It is like massively decentralized news aggregation.
You can just follow any-old tag and see what comes up, or you can try and improve the signal-to-noise ratio by following the people you generally enjoy reading and create specific lists.
I've also found it helpful in big conferences. at the WCC2010 I switched streams (there was 16) a few times because the quotes coming out of other sessions hinted that the other one was more interesting/relevant to me.
What it actually is is plumbing that you can configure more or less how you'd like. So it can be what you described. Or it can be any number of other things.
