As we've remarked before, however, a low capacity isn’t really an issue for a player like the iPod shuffle. 2GB is enough capacity to fit close to 12 hours worth of 320kbps MP3 files. While that does mean you'd hear a few duplicates before the iPod shuffle's 15-hour battery died, it's unlikely that most users would be unable to find a computer and sync some new playlists across in between gym sessions.
A greater annoyance is the continued use of a USB to 3.5mm jack adaptor for connecting the iPod shuffle to a computer, or wall charger. The proprietary dock connector on other iPods is bad enough, but at least it's ubiquitous enough that finding a spare cable, or a dock, to charge your device with is never a problem. The Shuffle adapter, on the other hand, is a small and easily mislaid item that is much less common place. Still, Apple tends to be pretty good about offering spares if you can ask nicely at the Genius Bar so it shouldn't be too big an issue.
What is an issue is the requirement to use iTunes. With the larger classes of iPod, we can forgive the symbiotic relationship, but on a player that doesn't need to tie into the App Store, can't play videos and barely needs any kind of library management, it's a bigger frustration. The iPod shuffle's type of portable, quick-and-easy to use MP3 player really needs to be drag and drop. And while we accept that many iPod shuffles are likely to be purchased supplementary to other iPods solely for use when working out - so the users will already be using iTunes anyway - it’s still frustrating.
Interestingly the iPod shuffle seems to mimic the improvements the latest iPod nano and iPod touch made to their audio quality. The iPod shuffle still isn’t going to blow you away with its lifelike reproduction of Beethoven's 9th, but it can definitely hold its own against alternative players.
Speaking of which, we'd be remiss not to point out how expensive the iPod shuffle is considering the feature set. The Cowon iAudio E2, for example, is comparably small and attractive, offers drag-and-drop music management and costs 25 per cent less than an iPod shuffle at only £30 for the same 2GB capacity. Or even better, the same money will net you a much-lauded (and rightly so) Sansa Clip which is simply, for want of a better description, a better player and hardly less portable.
The fourth generation iPod shuffle goes a long way to redeeming the failings of its predecessor. Physical controls make a welcome return, without making the device notably less portable or stylish. As ever, though, cheaper, more capable alternatives are available.