Why is One Format Better??

[STI Jaguar]

People are saying that dual formats- HDDVD and BD are fueling competition and lowering prices of Discs. So what would the advantage be if One format outright wins?

I am guessing initially that the prices will go up due to lack of competition but then will eventually drop very low due to volume and mass acceptance. I am not a marketing genius so is this pretty much how it goes?

Now is it possible to see duel format wars right to the end of the technological cycle- being HDVD and BD being around until the next generation format wars- like the next 5-10 years?