I’m at Gartner’s Data Center Conference this week, and I’m finding it to be an interesting contrast to our recent Application Architecture, Development, and Integration Summit.

AADI’s primary attendees are enterprise architects and other people who hold leadership roles in applications development. The data center conference’s primary attendees are IT operations directors and others with leadership roles in the data center. Both have significant CIO attendance, especially the data center conference. Attendees at the data center conference, especially, skew heavily towards larger enterprises and those who otherwise have big data centers, so when you see polling results from the conference, keep the bias of the attendees in mind. (Those of you who read my blog regularly: I cite survey data — formal field research, demographically weighted, etc. — differently than conference polling data, as the latter is non-scientific.)

At AADI, the embrace of the public cloud was enthusiastic, and if you asked people what they were doing, they would happily tell you about their experiments with Amazon and whatnot. At this conference, the embrace of the public cloud is far more tentative. In fact, my conversations not-infrequently go like this:

Me: Are you doing any public cloud infrastructure now?
Them: No, we’re just thinking we should do a private cloud ourselves.
Me: Nobody in your company is doing anything on Amazon or a similar vendor?
Them: Oh, yeah, we have a thing there, but that’s not really our direction.

That is not “No, we’re not doing anything on the public cloud”. That’s, “Yes, we’re using the public cloud but we’re in denial about it”.

Lots of unease here about Amazon, which is not particularly surprising. That was true at AADI as well, but people were much more measured there — they had specific concerns, and ways they were addressing, or living with, those concerns. Here the concerns are more strident, particularly around security and SLAs.

Feedback from folks using the various VMware-based public cloud providers seems to be consistently positive — people seem to uniformly be happy with the services themselves and are getting the benefits they hoped to get, and are comfortable. Terremark seems to be the most common vendor for this, by a significant margin. Some Savvis, too. And Verizon customers seem to have talked to Verizon about CaaS, at least. (This reflects my normal inquiry trends, as well.)