If you're not quite ready to turn your back on Fallout 3, you could always put your name down on a couple of petitions. While their effectiveness is questionable, every little bit counts. Heck, even if one person unaware of the issue takes an interest and agrees with our position, then it's worth the effort.
I've spotted two petitions so far - one on ipetitions.com and another over at Gameplayer. Give them a look-see, add your signature, and feel a little happier in the knowledge you've done something positive.
Alternatively, if you're on Facebook, reader Kent Dempsey has started an R18+ classification group on the social-networking site. At last count, it had over 600 members. Nothing like uniting for a cause!