I'm talking to you. Yeah, YOU.
You are misguided at best and malicious at worst. You're whining and crying about how you don't have more members on your Y!Group, which I will not link because that will only give you the publicity you so desperately crave. You had 130, until a few minutes ago when I (gasp!) left; even so, 129 members is a very respectable number. But oh no, you want to grow 250 to 300 members in the next year. There's nothing wrong with wanting, but...
I joined your group because I wanted to advertise my game, and I knew it was okay to do so there--after all, that's the point of the list, right? I won't advertise unless I know the plug is wanted and welcome, or at least that nobody will object to it. I don't want to advertise your group, and anyway, it's not really my responsibility to promote you. And even if I were going to promote you, it most certainly would not be on my group's main page.
If you want the group to balloon, fine, although I don't see a need--the archives are public and you have it set so that anybody who wants to post doesn't have to join first. Nonetheless, it's your group. You can do what you want with it. But I don't have to continue to be a member--and, given the tactics you've chosen to use, I've decided not to continue membership. It's not really a martyrdom for me, as I'm on a bunch of other groups and they've done all right for me in the past!
However, when you do things like this (taken from an Urgent Announcement of some sort, sent about earlier today, begging for help with spamming advertising):
I join, advertise, and leave.
This is why many of the GMs I know don't permit any advertising at all. Others, like me, have links configured so that only mods can post a new link. It's a waste of time for me to delete spamlinks in my groups, and it annoys me, and I'm not the only person who feels this way. I actually banned one clueless lackwit who attempted to join the OOC group for Terra Incognita, because a.) he clearly didn't understand the bit about membership in TI being a prerequisite for membership in the OOC group and b.) a quick search revealed that he was basically a spambot. I will ban you, too, if you try it in any of the groups I run, or will run.
Oh, and then there's your solicitation of other people to help you with the advertise-and-run shtick, and the harrassment of other people who have "roleplaying" listed in their interests while they're on YM. You know, when I'm on an IM system--very rarely anymore--I want to talk to my friends, not be spammed. That kind of thing, regardless of what you're promoting, will get you a one-way ticket to my Ignore list--and I'm not the only one.
If you want to increase group membership, there are ways to do it that won't annoy everybody in the universe.