From an armchair, it seems like it's a good idea to distribute a virtual server farm on multiple providers (Linode, AWS, et al). There's even libraries availabl

From an armchair, it seems like it's a good idea to distribute a virtual server farm on multiple providers (Linode, AWS, et al). There's even libraries available to abstract away the provider layer, like libcloud. However, IME it's typical to invest in just one provider. Is anyone currently using libcloud or equiv. and able to share details?