Late September and early October were some of the worst times I've experienced with The Inquisitr. Throughout September our setup with MediaTemple just kept getting worse (and our traffic with it), and nearly half a dozen hired "server experts" later we were no closer to fixing the (what we later found out to be an Apache) issue.
After the site was offline for nearly a full day, it was time for something radical, and that meant hosting where the only thing I had to worry about was the WordPress install vs the whole server setup. We landed at Rackspace Cloud sites, and nearly a month later (we joined October 5) it's mostly been a positive experience.
Rackspace Cloud Sites: The Good
Not having to worry about the server setup is a godsend every single day. The rules in the old days were if you got to a certain size, you went to a dedicated server. That's great if you really know what you're doing, but what happens when you start to outgrow your server, or more importantly your server can't handle big traffic spikes.
Rackspace promises unlimited scaling and that the "Rackspace Cloud handles growth automatically and affordably." So far, that has mostly held true. We've gone through a number of big traffic spikes (a recent Digg wasn't nearly as heavy as some of the others) and haven't skipped a beat.
The mention of it being affordable is also a huge plus for Rackspace Cloud Sites: although we haven't got our first month bill yet, it should come in at around $150. That's a full $600 less than the dedicated server we had at MediaTemple...and it all helps. I should note though that we've been hosting images on Amazon S3/ Cloudfront, and the bill there comes in at around $70/ mth, so make that a $530 saving.
I'd note that Rackspace does offer CDN services, and that's something we might consider in the future (Limelight has an Australian node where as Amazon doesn't) however I like the idea of keeping them separate at the current time because if we ever decide to move again, it makes the moving process that much more easier.
Rackspace Cloud Sites: The Bad
We've suffered two periods of down time in the last month (excluding the first day/ moving issues), one time may have been our fault, the second was downtime from Rackspace. I simply don't know what happened the first time (and I was on a plane to New Zealand at the time) but to their credit, Rackspace fixed the problem for us, well specifically for me at 4am New Zealand time from my bed at the Hyatt Regency Auckland.
Rackspace claims it offers "fanatical support" but I've found it to be hit and miss. Sometimes they are brilliant, and when we suffered our first outage I can't praise them enough. But other times you hit support staff that don't really care much about helping you. One time all I got from a support staff member was a cut and paste from their knowledge-base without any attempt to assist me in trouble shooting the issue. During our second outage, I waited on for 20 minutes, to eventually be pointed to a newly generated outage entry on their blog...with zero explanation of what was going on or when it might be fixed. Sure, they recognized an issue, but after waiting for 20 minutes surely I was entitled to a little more than a link.
The Rackspace Cloud control panel is minimalist and doesn't offer a lot of helpful stats; that's a good thing I guess if everything is running smoothly, but it's a burden when it isn't. Early in the piece we suffered from "Node server" issues. I think that it was something to do with our WordPress install, and we've cut back WP plugins to try to avoid these messages (every now and then though we still hit them.) Without access to processing stats, it's impossible to actually narrow down the problem, so you're left with trial and error (and the support staff cut and paste when you ask.)
The node issue is also a little strange given that Rackspace promises unlimited scaling; it is by its very nature a service capacity issue, so although I've found with the right setup Rackspace scales brilliantly, the proviso is that not everything is quite unlimited. Short version: you need to keep your WordPress install lean.
Despite the odd hiccup, I've got to say that I'm highly impressed in what Rackspace Cloud Sites offers, particularly at the price. Most days we don't have any issues, and the site purrs along through huge traffic spikes and quiet days alike.
If you're looking for hosting that scales and you don't want to go near a dedicated server, Rackspace Cloud Sites is a VPS service re-imagined to be something much better again.