I'm planning to build a tournament style poker app (ie only tournament play). My main experience is on a LAMP stack but the more I read about Node.js it seems like this would be a better language for this type of project. Which would be better php or node.js or will there not be a very significant difference? Thanks for the advice.
If you want to use a lot of fancy real time interaction with Ajax/Comet and want to support a lot of concurrent connections, I think that Node.js would be worth learning. There would certainly be no downside to it! Personally, even though I'm a PHP programmer by trade, I hate using it for large or complex projects, and it wasn't exactly built to scale.
If you have any experience with JavaScript, give Node.js a try. Maybe you around with it for a couple of projects first to evaluate it and get comfortable.