I'll also chime in on the Ask Away segment.

Roleplaying has improved my writing in some very basic ways, like some minor improvements to my grammar. I'm something of a perfectionist, so when I notice something that isn't quite right in my writing I'll investigate it and see how I've screwed up, then work toward fixing it. Roleplaying has helped this because it's a lot of writing I otherwise wouldn't have done and thus may not have caught so many little issues and mistakes that I made regularly, so it's sort of a practice makes perfect situation on that front.

However, roleplaying is such a different kind of writing that it's either irrelevant or has a negative impact on other kinds of writing. Unlike Chibisuke, I am in no way concise with my roleplaying (which is why I play in Advanced almost always), I let it go and have fun with it, and that helps my other creative writing efforts in yet another 'practice makes perfect' way. On the flip side, I've found that I have to purposely kick myself out of my roleplaying mindset when I want to write formal non-creative things because being expansive and creative there is generally bad. It has no impact on my general writing (such as OOC forum posts or talking to people on a chat service) other than the previously mentioned grammar improvements.

By the way, roleplaying writing experience isn't just automatically a boon for other creative writing, and in fact many people's creative writing is hurt by getting too much into the RPing style. Roleplaying is very different from writing a short story or novel or whatever in terms of goals and form, so if you can't separate the two and write them in different ways you're going to have some problems. Luckily my roleplaying doesn't negatively impact my other creative writing, because while I do suck at separating them I happen to lean the other way; I'm actually kind of shitty as a roleplayer because I basically write posts in novel/short story style (which is why my posts tend to be long) and then tack on something at the end to give other people something to respond to. Good, concise roleplaying is responding to whatever is going on around your character, then furthering the plot in some way. My posts often have a bunch of things that are only in my character's mind, thoughts or remembering past events, stuff that would be fine in a solo creative writing project but just adds a lot of bulk to my RP posts that other characters can't actually interact with (unless they're psychic or something). I've been trying to work on that recently, but it's just not in my nature to be concise or cut out things I want to say, so I'm just awful at brevity in general. For example, I intended for this post to be maybe 4 sentences at most when I started, and look where I am now. :lol