Most of the best looking games for the PS3 and XBox 360 (after over 5 years of development for these platforms) has difficulty running at 720p@30fps. While there will probably be a couple of games that are built from the ground up for 3D and make countless compromises to produce a good looking 3D title, it is unlikely that we will see any meaningful support for 3D displays until the next generation of consoles.
As for the cost of PC's to make them 3D capable, earlier this week Dell.ca had a 21 inch 3D monitor with glasses for sale for under $500; and you should be able to put together a system that takes advantage of that display for under $1000. If there is really any demand for 3D gaming it is likely that the processing power advantage and (dramatically) lower cost of displays will make it take off in the PC world long before it comes to home consoles.
