James,
Take a look at the Imac Buyer's Guide then decide for yourself.
http://guides.macrumors.com/iMac_Buyer's_Guide
There is a lot of speculation and rumor of an update but no one knows when it might happen.
The general thinking going on is that if there is an update it would be minor meaning a switch to the Penryn Processor (and therefore a minor speed bump), probably 2GB RAM as standard, and maybe a bigger Hard Drive.
The number one thing that has most of us waiting is to see if there is an update or change to the graphics card. The current graphics on the IMac is not bad but not great either.
Others are hoping that there might be an option for a matte screen instead of the glossy and some of the really hopeful people are waiting to see if it would include BlueRay which is very doubtful.
Other then that there is not much that else that might happen.
You should check out the refurbished section of the
store where they have some great deals going on refurb models.
Personally, I have been waiting for over 2 months now. I have a pending order for a refurb but am holding off for the refresh. I am hoping that it would happen before the 15th of April otherwise I will likely just go forward with the refurb.
You have to decide how long you are willing to stick it out. Seems that everyday that goes by with no new news or updates gives credence to some people's belief that the updates won't occur until the WWDC conference in June.
Good luck to you.
