Eh, with the plethora of DAC SFP+ cables at extremely affordable prices I don't really see many people using CAT6 - especially considering the substantially higher power draw that 10GBase-T has over the DAC's.
This doesn't quite fulfill the role either though...
A quick search for SFP+ cards that can handle 10Gbit/sec shows that the typical price is ~200 USD/card right now (this is still at least 3x the cost per card I'd prefer to see).
Given the pricing on individual cards I'd hate to consider the price of a switch, if such a thing even exists.
We're talking about datacenter usage, not home. Also, there's plenty of older generation cards out there at reasonable prices, the Mellanox Connect-X 2 cards I have in my home servers cost me like $40 for a pair of them. And no matter how you slice it, 10GBe switching is expensive right now, like, crazy expensive - to the point that I don't even bother with it and my VMWare box is connected directly to my FreeNAS box with a 1M SFP+ DAC as a switch with even two 10GB uplink ports would have cost me considerably more than my cheap 24-port TP-Link managed switch ($150).
A quick search for SFP+ cards that can handle 10Gbit/sec shows that the typical price is ~200 USD/card right now (this is still at least 3x the cost per card I'd prefer to see).
Given the pricing on individual cards I'd hate to consider the price of a switch, if such a thing even exists.