Power may be a bit quicker than Intel, but it's unfamiliar to many. Nvidia is breaking new ground, it's sexy, accessible, and cheaper.
On the software side it's a similar story. Why use their unknown proprietary cloud stuff when I can just make use of the plethora python/julia/clojure/R stuff? AWS is fancy and ever expanding, Softlayer is a PITA.
IBM biz news http://finance.yahoo.com/q/h?s=ibm
BlueMix is a branded version of Cloud Foundry, which is an opensource product owned and managed by an independent foundation.
Disclaimer: I work for Pivotal, another company that works on Cloud Foundry.
The support I have received fromAWS has been literally stellar over anyone I've ever worked with.
Even now, my previous rep got promoted and moved on from account mgmt but if I send him a one-off question he gets it answered and taken care of immediately.
I have literally out of hundreds of calls and meetings with aws been disappointed with one call. That was when I accidentally changed my root account email address and I couldn't recall which email I had set it to, so I clicked the "contact customer service" link from the forgot password page and it connected me with the "Amazon.com" (shopping) customer service agent who apparently had no fucking clue what aws was.
Note that this does not mean that I think it's optimal, but I do mean that a vast majority of enterprises have a form of group-think culturally that makes this approach something that's demanded as a standard service offering that is no different than developers expecting APIs from a hosted service.