I really don't get why people don't seem to check the manufacturer's web site for reference.
You can always get full specs for any current model at Blackberry.com. If a feature isn't listed it's not on the device. Pretty straightforward IMO.
...and FYI, WiFi equipped models tend to follow this model number convention: xx20. In other words, the 8120, 8320 and 8820 have WiFi.
No telling if RIM will stick to this but it's a handy rule of thumb.