I dont think devalued in jobs listing ! it depends upon your skill , your profile rate and your portfolio . One thing matter most which currency you are belongs. If your are from UK , USA or any economy driven country $10 to $15 p/h might be not affordable but if you are from other country where dollar( $ => local currency) value matters.
Well, I live in Argentine, I've been programming for about 10 years, worked in big companies like Travelocity and I also have a great resume. And working as a freelancer, I'm charging U$S 25-U$S 30 per hour, and some of my customers think that it's too much so I charge them with U$S 10-U$S 15 per hour, but actually work one hour and submit two ;) They don't see the difference (because of my experience, I usually do in one hour what other developers do in two or three...)
Anyway, that's good money in Argentine, U$S 30 = AR$ 111
What's the common rate for rails developers?
The site is actually limexchange.com and those ads may not be spam cause you probably see their banner on the top of this page right now. So it may be a valid promo campaign that supports the WWR website.
Ricky, most of those ads actually kinda "promote" one of those sites for freelancers (like getafreelancer.com, etc). So they are not real ads (actually spam) and should not be considered as a tendency in terms of rates.