I wasn't surprised that Apple announced revisions to the iMac line, having seen some clearance sale adverts from Apple resellers in the last week or so.

Apple probably didn't warn its resellers, but they have become accustomed to reading the entrails of stock figures and delivery times.

Anyway, faster processors, memory and graphics are nothing unusual in a 'speed bump' update like this. For most customers, support for SDXC memory cards is probably a 'future proofing' move as they don't yet own a digital video or still camera that support these extra-high capacity cards.

64GB SDXC cards currently sell for around $A300 - expensive, but about half the price of a similar amount of memory in the form of multiple 4GB SDHC cards. According to Panasonic, a 64GB card can store around 8.5 hours of HD video at maximum quality.

Some people are probably getting excited about the Mac Pro refresh that offers various CPU combinations from a single 2.8GHz quad-core Xeon to dual 2.93GHz six-core Xeons (prices start at $A3499), or the 27in LED Cinema display (2560 x 144 pixels, iSight, microphone, speakers, powered USB hub and integrated MagSafe charger, shipping in September).

But to me, the most interesting part of Apple's announcement was the $A99 Magic Trackpad, an external version of the multi-touch trackpad that's been part of the MacBook family for some time. I've been expecting an equivalent for desktop models ever since multi-touch arrived. I'll have more to say about it when (if?) I have a chance to test one.