You'd think so, but it has been quite a while and nobody has heard anything from Skype, specifically. There is only one VoIP app on the app store right now, so I guess it really hasn't caught on yet. I bet anything that there will be a VoIP program for the Touch, but whether it will be Skype is up for debate-
On the one hand, larger companies tend to tread lightly and slowly- which could explain its absence from the App Store.
On the other hand, it has been so long that even Spore has an app for the iPhone/iPod Touch, and we know those guys are slooooow.
You'll just have to wait and see- contact the guys who have the only VoIP app on the store (TruPhone) and ask for iPod Touch support if you want, it never hurts to ask (see
this thread)!