Ars Technica review of the new iMac: http://arstechnica.com/apple/2013/09/new-cpus-faster-wi-fi-same-flaws-apples-2013-imac-reviewed/2/
I will admit to not being an apple fanatic. I think they build decent products that are relatively intuitive. But they do not offer the upgrade ability I like with my desktops, and this years IMac does not sound any different. Although the upgraded CPU and graphic cards will offer a nice upgrade to anyone with a pre 2012 iMac, it doesn’t seem like its anything to ditch last years model for. It might even be worth seeing if you can get last year model on a clearance deal.
I was a bit dissapointed to hear they made it overly difficult to upgrade the RAM. It puts customers in a tough spot if they were wanting to upgrade in the future and seems like a bit of a money grab.
Despite a few disappointments and odd choices, the new iMac still seems like a good computer with a few years of life in it. I suggest reading the full article on Ars Technica that was linked at the top of the page.