wouldn't read much into IBM's purchase
Myself i wouldn't read much into IBM's purchase of that service provider with regards to openstack. Openstack is still a maturing product, and it makes sense that only a few large providers have jumped on board at this point(I'm sure many others that are working on it still have relatively small implementations relative to non openstack deployments in their org).
That company IBM bought by contrast had a mature provisioning and management system for their setup. Maybe it is getting long in the tooth for today's public cloud stuff, it really seems like they are more of a managed server provider (what rackspace used to specialize exclusively in) with perhaps some cloud on the side.
I'd expect them (over time) to migrate to Openstack for at least portions of their customer base that can live within that model (the openstack model is similar to amazon's design, which it makes it a poor choice from an availability standpoint for most businesses). Other customers will likely remain on physical servers because that's what works for them(often times running on physical hardware is treated like it was something bad, if you can properly leverage the underlying hardware then there is little reason not to go physical). Others still will go for more advanced infrastructure or perhaps a hybrid.