The age of Internet inundates us - there's an information overload in progress. You indexing all this stuff takes a load off your readers shoulders. People like news, geeks like geek news. You keep them interested. It's another form of content that you can deliver. This is the positive way of looking at following trends and it builds loyalty from the people who know they can come to you for that information.
You can find these stats and others by visiting http://draft.blogger.com and clicking "Stats". I wrote a single post on New Eldar Unit Rumours (cause I totally taste the rainbow) and look at this list of top all time search keywords - and that's from one post. These days, a single Grey Knight post could net you a few new visitors.
By the way, don't forget to credit where you get your news from - more on that in a later post though.
Secondly, keep in mind that there's a lot of sites out there talking about news. You might actually alienate your readers when they have to read through a bunch of blogs all reporting the exact same information. Sure, you can add your own unique view on the information and being the first to report something can be kind of cool, but by the time most get around to reading it, you'd still be just one of many. One way to temper this would be to only report on larger news pieces, so you're not constantly pouring out news.
As Old School Terminator also points out, images are another way to gain extra traffic through this method. Just as many people search for images of this stuff as they look for textual information.