Yep, I'm afraid WiFi is not present on the AT&T version. The generic one has "WiFi" and "GPS" printed on the right side. The AT&T version just has "GPS" printed in that spot. It's also nowhere to be found in the menus, etc.
The AT&T unit may not support this, but unbranded units almost certainly do. Unbranded w300, w350, and w580 all had full email clients, but the AT&T version did not. The review should state in the title that it is a review of an AT&T-branded phone.
AT&T replaces it with a POS email client which only accepts certain services, and lacks push support and other things.
Also, I am not sure that this sentence makes any sense: "The messaging services were improved with the addition of support for more IM clients"
The "client" is the software on the user's handset (or the entire handset itself). Maybe you meant "services"?
"Client" is a term that could be used either way, in my opinion. It does sort of act like there are three different IM programs on the phone. Once you sign into AIM, it becomes the AIM program, with an AIM in... (continues)