I honestly don't think I could pick a favorite if you paid me. There are so many equally cute dogs here on PT, if I attempted to list all the ones I thought were the "cutest", my list would be a mile long!
I do adore Freckles (Finn's Mom posts pictures of her sometimes), though. Then again, she looks an awful lot like my Ethan, so it might be part of the reason, but certainly not all of the reason!