A good avatar which reflects your niche can help to advertise your forum and keep your brand consistent from site to site as you move around the internet promoting your site on various forums.
Avoid cute or silly avatars (unless this matches your forum's topic) or ones which come from the forum database as they are likely to be duplicated by other members.
Taking time to have a professional avatar designed that matches the colors or theme of your forum is a good way to maintain the consistent image you are trying to portray. When allowed, incorporate your forum name into the avatar or use other logo images that are instantly recognizable as belonging to your forum or site.
If you are a blogger, you might consider using the same personal photo that you've had posted on your blog or Google+ page. This will help brand your own image in the reader's mind.
Eh, using your avatar as advertising space just feels incredibly cheap and superficial to me. When I'm posting content on a forum or blog, I want to sell myself and have people know I am genuine, and therefore my site is also genuine. Most sites allow advertising in signatures so people just expect that, or don't really care if you do, but avatars are meant to expressions of yourself as a human, and using that to just boast your website makes you seem, in my eyes, completely fake, and may end up leaving you with fake visitors because of it, opposed to people who like you as a person and want to know more about what you do.
I'd rather sell myself as a genuine person when I put up my content, so I'll reserve my avatar to stuff that expresses me, such as my current avatar - Ema Skye from Ace Attorney, because I love her character the game series.
I will have to give my wholehearted support in fantanoice's direction.
I am really not fond of advertisement avatars and especially users that name themselves after their website. It reminds me too much of spambots, and I know all of us webmasters aren't particularly enamored with those. All it really does is put up an artificial mask that makes one unable to appreciate the person behind it, and I always find myself in complete disregard of them.
It's best to use a unique pseudonym for yourself, in my honest opinion. It will give you a face that others can recognize as an individual personality, and if you build up your respect at a forum, you will find yourself drawing much more potential eyes to your website; far more than an advertisement avatar and username will.
I'm not fond of people using their avatar space as extra ad space.
I mean if they want to put an ad for their site in their sig? Fine. But putting one in their avatar is kind of redundant and pointless. Plus it comes off looking tacky and like blatant "Hey look at me" advertising.
Furthermore, if the avatar is a flashing gif with their url... then I would likely remove that without a second thought.
Also, I will fully admit up front that someone who joins my site with their name as their url will either have their name changed for them or be forced to change it before they can participate on the site. I do this because using their url for their name is a form of blatant advertising that I do not allow. Plus many times people who put their url for names can't even hold onto their domains so they end up getting bought by someone else and turned into another, completely unrelated site from what they originally linked to. (In the past this has lead to game sites becoming porn or malware sites.)
Avatars aren't effective advertising methods because you cannot click on them and be redirected to an external website.
Avatars are just a space filler really. My current one has no real meaning behind it. I was just browsing an avatar website and picked it. I change it from time to time.
The avatar says that I am an Age of Sail fan. And yes, I admit it anyway. The actual advertisement is in the signature. And the name... is mine. Got baptized with it.
I share the idea that avatar is one thing about user profile that shouldn't have anything to do with advertisement. To me, avatar represents myself or what I like, which can be related to the forum/website I advertise for, but doesn't have to be related. I completely agree that it can be used to show how genuine we are, and that we are human not bots.
It says something about you at that particular moment I guess. I think a lot of people change their avatars regularly, and as they are becoming really common, quite randomly too. I've noticed a change in my own self over time. The answer is, it says something about your aesthetic, but maybe not much more.
