As a user I don't feel the need for multiple newsfeeds. The people I'm friends with on Facebook (and pages that I have liked) appear on my newsfeed for a reason - because I'm interested in seeing what they have to say. If I don't want to see certain posts, I remove or mute the connection!
I can, however, see why people might like the idea. If you're looking for something in particular, or follow a huge amount of accounts, it is a nice way to separate/filter updates.
Does this mean that businesses have more or less chance to be seen? It's hard to tell really - they're either going to be lost in a feed that someone never checks, or will be seen more often in a feed with fewer, but more targeted posts.
Why is Facebook testing multiple newsfeeds? Well, for many reasons. First, more available ad units equals more revenue for Facebook, whose $12.5 billion in ad revenue accounted for 92% of Facebook’s total revenue in 2014. Second, it’s one of the many features that both users and Facebook wants. The days of endlessly scrolling from one category of content to the next might soon be over. If this becomes our Facebook reality, it might be much more like a newspaper, where sections are designated for specific categories.