Richard who is by far the leading VoIP expert in Austria has a post that should be of interest to VoIP companies wanting to put their service into Austria.
Really it's more suited for carriers who want to issue Austrian numbers. Here's why.
IP knows no boundaries.
If you're a customer of any broadband phone provider and you take your Telephone Adapter (that's the box you plugged into your router or between the router and DSL or Cable modem) your number is wherever you happen to be. If you're using a softphone as your end point, then you're number is wherever your PC or PDA happens to be.
I'm sure hoping that forward thinking nations never start thinking backwards as some countries already are and block or restrict the opportunity for global brands of telecom carriers to exist. We are already hearing reports about Telmex blocking VoIP traffic. If other nations jump on this bandwagon, and some already have, the "portability" of VoIP gets stopped dead in its tracks.