Many large and well established forums when I register and confirm I get a default welcome message and welcome PM. I never like that and I have always used more humanly custom email because it helps to develop relationships, to deliver value added content and to communicate with your audience. Check out my latest blog post on how to write Effective Welcome Email for your website / forum / blog http://www.codeitwell.com/write-welcome-email.html
I think this also depends on niche you are working on and the traffic you get . If you get targeted traffic on your niche and delivering good important info than its ok for them .
LOL, how come welcome email affects niche.... LOL Welcome message has nothing to do with the niche.. the OP is talking about professionalism..
Exactly. When I see the default welcome message I can be rest assured for 2 things. 1. Admin is not serious about the forum. 2. Forum may go out of business soon because there is nothing done apart from putting it online and work on getting some articles from here and there.