You don't often hear about Rackspace offering to match the prices of its competitors, but that seems to be exactly what they are claiming they will do on their website. I'm not sure when this came into operation, as I only just noticed it today.
I talked to them and they do say they would much the price for services that match their services. For instance, my hosting offers 99% uptime while Rockspace offers 100%. So that is not the same hence they would not match the price. On top of that, maybe they are as good as they say they are, however, they are very expensive. So don't put your hopes up
There are some good web hosting comparison sites around, we generally look at Hosting Picks (www.hosting-picks.com) for price and service comparisons and then do further investigation