Desirable goods
The reason the shops are so crowded, is because most people want an iPhone, IPod or IPad, along with the inevitable accessories that go with the devices.
A secondary re-action, that happens to many people who buy one of the portable devices, is the consideration of buying a macbook or imac.
I've seen this happen to several 'PC users' in the office - they get an iPad and a few months down the line, they replace the family PC with an iMac. (assuming they've got the readies, that is)
Only a close-minded PC fanboi would deny that Apple products are made well and look cool.
Yes, yes, the old argument, you can get more processing power for less if you buy a PC, or build your own, is bandied about - but that's only viable for those that a.) Give a damn and b.) have the skills to build.
Most people want a cool looking bit of hardware that works for them, with the added (albiet paid for) bonus of an Apple Care plan for the first 3 years. It goes wrong, just take it to the Apple Store - easy.
El Reg is read by geeks, myself included, but we have to remember very few people share our enthusiasm for computers.
I've never bought anything from an Apple Store, I built my own machine capable of running MacOSx for a fraction of the retail price of a new Mac, did the same with my DVR, creating a Mythtv/BOXEE combo that wipes the floor with any commercial DVR - but I'm a geek - I have an android phone running Cyanogen.
Apple is desirable, hence the stores are crowded. Many punters will be just going to browse and will then buy online - whichever way, Apple has a winning formula that seems recession proof.