Should I wait until after Macworld Expo?

Why not? At least get iLife 07 for free if you can wait.. even better, get it in April so you may get Santa Rosa as well, even better still why not hold out till Paris next year and get the new 45nm chips?

 

A lot of information in that article is out of date and no longer correct.

However, it is almost certain that Apple will update iMacs in the first quarter of 2007. You can expect updates of the iMac 2-3 times per year, now that the transition to Intel is complete. So, there will always be something better a few months down the road.

IMO, there will be only evolutionary changes in the iMac for the next year or so, nothing revolutionary. If you think the iMac will suit your needs, now is a great time to get one!

The best reason to wait would be to get OS X 10.5 and iLife '07 free.