A familiar, as most of you know, is an animal companion with magic powers given to it by a mage. So my question is, can you talk to your familiar? I looked it up on the WoW wiki but I couldn't really find anything on that. If it's possible, is it telepathic or what?
I'm going to say it depends entirely on the type of familiar. I RPed extensively with a mage who had a familiar back before restart, he had a small penguin that would peek out of his sleeve and crawl around at times, but I never once saw him speak to him intelligently like a human would to another human but more like a human would to his pet. But at the same time, being in a world with so many bizarre beasts and beings, I wouldn't say it's out of place at all for a familiar to speak with its mage either verbally or telepathically.
Just be careful with how you do it and how you use it. Some might be quick to cry "Metagamer!" without knowing exactly what's going on. I had a buddy who had an IC raptor pet, not even magical, and he would communicate with him in a manner similar to how any pet owner IRL who is close to their pet would. You can just detect subtle hints in their behavior, and sometimes it's not subtle at all, to know what it is they want or how they're feeling etc, but people would simply refuse to understand that and make a big deal out of it.
I've always seen familiars as companions that should be cared for, although they may have some utility. I've never had a familiar out of my sight as they're not suited to combat and are, generally, a valued friend of the mage. People tend to notice magical beasts and peculiar animals lying around, so it's difficult to spy on someone as is.
If you're going to communicate with a familiar I suggest RPing it as a whispered conversation in the mage's native language. Telepathy, for me, has always been a dodgy subject. If the owner of the familiar is able to use telepathy then that's fine. If you're a priest you could also use that spell, I forget the name, that allows you to see from the recipients POV. Short range telepathy (i.e. the distance at which two people could feasibly talk with raised voices) would probably be fine in my book. I don't like the idea of long range though (although might be okay if the familiar's master is pretty powerful).
Either way, when having used a familiar in things like NWN (never tried it in WoW) I treated it as an old friend and not some expendable object so would always keep it close by.
Edit: By 'mage' I mean anyone with a familiar. Force of habit from NWN/D&D days. It's shaman and warlocks that get familiars in WoW, isn't it?