Storm Raven said:
In a coldly objective world, probably not. In reality, many potential customers and future publishers will assume it does. "Couldn't print a real book, huh? You must not be a real writer."
I think such a publisher would be very foolish. A persons writing skills are not measured by where he has his name printed, but upon the skills he has.
I think that in general, what you are describing could be the reaction of people not in the process of hiring a writer, but more of general reaction from other people.
On the other hand, it is a stamp of professionalism to have been published in print, and it might break the ice at initial contacts with publishers. But I maintain that any publisher who decides who to work with based the difference between "print" or "online" credits is foolish.
Even in print is easy for someone to get a writing credit, if you have the right clout or the right friends. I've had people in management tag along on texts I've written, for example.
So just because someone says they're a writer and they've been published in print here and there, no publisher worth his salt would take that as evidence of anything without checking the writing skills by requesting a sample.
But, there are differences of course. Just as it is more impressive to have been published by WotC than having cranked out your own photocopied fanzine, so it is more impressive to have been published by an established publisher online (such as NY Times, or WotC or what have you), than just cranking out your own blog.
Your self-published work online would become a strength to you only after keeping up with it for a couple of years or so. So in that respect you are correct. No one is going to be impressed if you whip up a mail saying "I wrote this on my blog". They might give you a second look if you said "I write online for WotC".
I find that the thing that makes for the best stamp of approval is to say "people pay me to write stuff". Then a publisher will take a bit more notice, because if someone is paying someone to do something, then there's probably quality in there, somewhere.
/M