apples vs apples
To start off - I don't work with NextIO or sell there stuff.....
Do you think that NextIO may have used 1U servers with a little more "oomph" than the single dual core processor with 2GB memory blades that you configured.
Where we've been involved in building infrastructure for hosting (including one that used NextIO), we've been using multicore processors (minimum hexacore, sometimes 12 core) with multiple sockets in use (sometimes quad) with tons of memory - VM density is normally limited by the memory you put in.
In NextIO's example they had approx $200K on the "grunt" server hardware itself (i.e. excluding switches, blade chassis, etc, etc) based on this part of the article:
"the cost of the servers and the Maestro PCI-Express switch together, it costs $303,062, with about a third coming from the Maestro switches and 60 PCI cables."
The "non-compute" blade infrastructure according to the basket you produced had a cost of ~$130K, so I'd be comparing that against the $101K for NextIO - is it enough of a saving? It might be for some people and it is certainly lower cost and doesn't have vendor lock in that blades do.......