Is anyone else having the same issue with these services as I am - namely that Rackspace Cloud (and Amazon Cloudfront) do not support gzip compression? That means that any advantage in latency that you gain from serving a file locally is offset by the fact that it must be served uncompressed. It seems like it should be an absolute requirement for any CDN provider (and the smaller ones like SimpleCDN and MaxCDN do support gzip). I've repeatedly asked Rackspace if they plan to support gzip and they haven't given any indication that it's coming; this e-mail confirms it's not even on their roadmap.
This has been a big issue in the Rackspace Cloud user community. There has been no support for CNAME, SSL, or invalidation, so lots of customers (including me) have looked to other providers. I moved all of my projects to Amazon Cloudfront for this reason. Hopefully with the move to Akamai, Rackspace can play some serious catch-up feature-wise.
If you are interested in CDN performance comparison as seen by end-users take a look at our Charts: <a href="http://cedexis.com/data/charts.html?country=223&providerType=3&chartType=all" rel="nofollow">http://cedexis.com/data/charts.html?country=223&provider...</a><p>Gabriel (yegg) wrote about our services on his blog -- <a href="http://www.gabrielweinberg.com/blog/2010/12/testing-cdn-performance-via-cedexis-radar.html" rel="nofollow">http://www.gabrielweinberg.com/blog/2010/12/testing-cdn-perf...</a>
We've got 500K objects on Amazon and any one of them needed to be accessible via SSL. That and the price made Amazon an easy choice from a myriad of competitors.