I don't see how I can put it as an option if my MSN/WLM can't stand videochats.
Most of the time I use it, it freezes like crazy and faints more than Tinychat. A lot of the remaining times, either audio or video doesn't work. And I know many other people who got such problems (especially since Windows Live Messenger as in some of its versions the videochat option didn't work at all or was bugged by default).
In case I'd offer WLM sessions, I must add at least 30 minutes to each session due to technical problems. If there is something I hate to lose, it's time.