Well wireless or cordless is up to the manufacture whichever sounds better to them I think, so it does not really corespond to a specific techno, but you are right there are 2 types of non-corded communicatiob between pereferal and receiver. Logitech and MS use Radio wave technology which measn complete freedom from wires but withing a specific radius from the receiver. The IR ones can be used further from the receiver but has to be pointed at it at all times to work and not recommended. There are 2 versions to the iTouch, I ahve both and the one youa re looking for is the Cordless iTouch, which I have, the other one which both me and Mem have is the Corded iTouch with 2 port USB hub built in, which is not the one you are looking for.
If you want gaming then get the Cordless iTouch keybaord separately and then also get the Logitech Optical Mouseman Wheel mouse. That would be a pretty much perfect combo. About over 80% I would give for that setup in gaming, for hard core you will need a better keyboard but it will do because you will only be pressing so mabny keys in one go and will not over load it or anything, just keep an eye on the battery power.
Hope this helps you even more 🙂
Albert.
EDIT: DOH! Beaten to it by Bigsmooth, but I guess confirming it is no harm, but I hope the rest helps 🙂