>Walk in to any datacenter. HP and Dell absolutely dominate. Third place is Sun. Fourth is Supermicro.

This is also what I thought. (though, places I've worked, ODMs and supermicros dominated, followed by dell, with hp dead last, but yeah, the quote from IBM never even made it to technical evaluation where I would see it.)

However, I went looking for a source[1] before I posted further up this thread. Apparently, IBM sells more servers than dell or hp (but not more than both put together)

Hm. reading further, I see numbers between 10% and 30% of IBM's server revenues being the high-end stuff they are keeping. So that could bump them below both dell and HP, in terms of just x86 servers, but even knocking 1/3rd off, they still sell a lot more x86 than I thought.

[1]http://www.forbes.com/sites/chuckjones/2013/08/29/ibm-regain...

I'm not sure where you make up your data from, but if that's the case, you might be going into a lot of low end data centers.

http://slashdot.org/topic/datacenter/idc-server-market-slowi...

Obviously my data is anecdotal, but I really haven't seen much IBM hardware deployed in communal datacentres (e.g. Peer1 or similar).

If IBM's selling that kind of volume, it could be to governments and other large enterprises with private datacentres.

Then again, that's revenue, so for every IBM server there could be five commodity Dell units in the rack and they'd have the same net cost.

This is true, and I believe you are exactly correct. IBM is catering to private data centers and not ones that you or I would be renting a rack in.

iDataPlex clusters are somewhat more common in HPC environemnts. They are x86-based.