People, The Mango Wi-Fi tethering(you need mango for this) is based off of hardware chipset with a combo of software.
[LIST] Devices that CAN, CAN'T or HAVE WiFi hotspot support - xda-developers
The HTC Trophy and the 7 Pro (Arrive) does have the correct chipset (BRCM 4329) that will support Wi-FI tethering. (I only care about the Trophy really...sorry but, I like to help)
The problem now is software on HTC devices (Samsungs included the software driver) that did not come on upgraded devices. It's the SoftAP drivers and registry edits that claim will solve the problem.
I would watch this thread (as I have been and have a buch of posts in it), it's manly about getting "Mango" wi-fi tethering working but, there is HTC people in there trying to see if they can get it working.
Mango Internet Sharing/Tethering - Omnia 7/Focus Tutorial Added to OP - xda-developers
It's a interesting read, if you really wanted to have an idea on what is needed to get this working, it's a fairly good read, all 48-50 pages of it..
Based on how it works, I feel once the GSM models are figured out, I think it will work on CDMA models. It's just using the current data connection from what I see.