Today was an exciting day for Apple enthusiasts, as the company revealed the iPad mini, a new Mac mini, and an awfully gorgeous new iMac line-up. But as is so often the case with technology, innovations in overall size can mean the loss of features. Apparently, the 21.5-inch iMac doesn't contain easily switchable RAM slots.

During today's event, Apple showed off an almost impossibly thin iMac. Seriously, it's amazing what Cupertino is cramming behind that beautiful glass display. The new iMacs -- in 21.5-inch and 27-inch varieties -- are shipping in November and December.

But as noted by Cult of Mac, the 21.5-inch iMac doesn't feature upgradeable RAM. The smaller model comes with a standard 8GB of DDR3, and is configurable up to 16GB. The 27-inch model, however, features four "user-accessible" SO-DIMM slots. Again, 8GB is standard on the 27-inch model, but it's configurable up to 32GB.

Clearly, the 27-inch model can hold the extra RAM access, thanks to an additional 5.5 inches of internal space. 

While this may not sound like too big a deal to the casual user, iMac owners seeking to extend the life of their iMac -- in terms of power -- will likely do well to consider the 27-inch model; especially since Apple yet again failed to reboot the Mac Pro line, today (bummer). 

As we previously noted, both of the new iMac models drop the optical drive all-together -- another consequence of the thinner display. If you're the type of person who still requires the occasional disc, probably a good idea to grab an external SuperDrive.  

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