This eWeek article has where they quote "Douglas Crockford, a JavaScript architect at Yahoo and the man behind JSON, the JavaScript Object Notation" as saying he wants a new browser war since it spurs innovation and drives the web forward.  I agree with that statement wholeheartedly.  Crockford is quoted as also saying that all the bad things that happened in the last browser war (proprietary extensions, poor standard support, etc.) will not be repeated because of market pressure and standards.  First, I think the standards argument will never fly.  Almost by definition, standards rapid innovation do not mix.  Neither Microsoft of Google will wait around for the standards process to make feature X a standard before implementing and heavily promoting it.  I don't see "market pressure" is going to work either.  The market has complained about IE 6/7 standards issues for ages but the market continued to make exceptions for them.  If something is popular, content producers will support it.  When Chrome starts to capture more market share content producers will leverage proprietary features to give visitors a better experience.  Its a simple game - if you don't support feature X, no matter how proprietary it is, but your competitor does and it takes away visitors from your site because feature X gives people a better experience, you either support feature X or you lose.  It won't take long for someone significant to break ranks (either on their own or as a result from financial incentives from the various vendors) and the game is afoot.

I think a new browser would be fun to watch and be involved in - but be careful what you wish for Mr. Crockford. ;-)