Cats do say "blurt" not "meow". Robert A. Heinlein says so, and that's good enough for me.
Now--why do I mention this on a writing blog? Because there has been some talk about "old-fashioned" writing on some of the writers' loops. Old-fashioned in this case can mean practically anything--writers who are in their 60s trying to give their 20-something characters authentic voices; Jane Austen's style as opposed to modern; and historical writers attempting to get their characters talking right for their age and still be understandable to a modern audience.
Always, when writing in another era, there will be something lost in translation. My just-finished WIP is a case in point. In the 14th century, the upper classes spoke either middle-English or Norman French. I can't write in either language--it wouldn't communicate. Even if my skills were up to it, it wouldn't work. Writing is, after all, primarily about communicating.
That said, my characters can't sound 21st century. Not having been there in 1353 to hear how folks spoke, the best I can do is an approximation of a 21st century author's guess at medieval usage and speech patterns.
(I refused throughout the book to use 'tis. Just my prejudices coming through. I'd rather throw in an obscure French term, or even Cornish, than use that tired old contraction. To me, it shouts "Hey, this is a piece of historical fiction and I'm too lazy to guess how they REALLY talked, so here's 'tis' to tell you so!")
Now, some folks are not going to like the guesses and choices I've made. That's fine. If they get the gist of the story, I figure I've done 99% of my job. If my cat says "blurt" instead of "meow," I hope you will enjoy my story anyway, and forgive the fact that my choices aren't quite what you would've chosen.