Ancestry doesn't feel the need to inform their members of new features. I guess they figure that since genealogy is a hunt anyway we're all good at ferreting out new features on the site. and yes I'm being sarcastic.
If you step back one level in the forums to http://boards.ancestry.com/topics.dnaresearch/mb.ashx
you'll see a forum about the atDNA results as well as one for what is jokingly referred to as their "ethnicity results". The members who participate in those forums generally keep each other informed about new things we discover on the site as well as things like GEDmatch which fortunately are out there to fill the voids that Ancestry can't seem to fill. There are a lot of interesting threads on both forums.
Be sure to post your GEDmatch kit# to the appropriate thread so others can see if you're related. you'd be surprised at how many of us are even if the relationship is somewhat tenuous.