A co-worker was begging me to read a book a while back. I told her I'd get around to it. Here's all I remember about the plot:

Humans have been visited by extra terrestrials. They have no problem blending in on Earth and observing us because they just happen to look exactly like housecats. Yes that's correct, kitties.

I'll admit my first reaction was "WTH, really?" *eyeroll*, then I quickly forgot about it. 

Since then I've overheard a couple of strangers apparently talking about the same book. At least I think so. How many books about hyper-intelligent space-traveling housecats from another galaxy can there possibly be?

Now I'm intrigued. So, who can name that book?

No Tom, I don't think that's it. These cats fly spacecraft and whatnot.

Anne McCaffrey's Barque cats in Catalyst?

Anne McCaffrey's Barque cats in Catalyst?

that's the one i thought of too.  however, while they do visit human planets, i don't think Earth is one of them.

did the co-worker give an idea of whether this was a newish or an older book?

Is it this one?  I haven't read it yet, but the description sounds likely.

http://www.paperbackswap.com/Outworld-Cats-Jack-Lovejoy/book/0886775965/

Could be the Chanur series by CJ Cherryh.  They are about space faring Cat-like aliens.  Actually pretty good stories.  I think there are four or five in the series and they are available here on site.

Anne

NOT the Chanur series- the aliens are cat like but not actual cats. And they never visit Earth. If you haven't read the Cahnur book, I would recommend them. Not hreavy on action, but tense political overlay, and a very believable universe.

If the plot also included aliens who look like trees and speak with British accents, angry Inca indians from another dimension,   and Monitors from the Galactic Union (in the form of cats) then you want "Cat-A-Lyst" by Alan Dean Foste. 

This is probably obvious but would it be "The Cat from Outer Space" by Ted Key (it's related to the Disney movie but don't know which came first)?  I know I read several books of this nature back when I was 7 and over but don't know what the titles were.