Both leisure spending and leisure time are finite. Sales of video games, for example, have risen unfailingly over the time period during which music sales have declined. This logically means people having both less money to spend on music, and less time to spend listening to it, which would equally logically cause a drop in music sales which had no connection whatsoever to filesharing. (Also, there's probably a case to be made in regard to the vastly increased complexity of today's games compared to even five years ago, and hence the increased amount of leisure time which would be taken up by them even if the amount of financial spending was static.)

The main music-buying demographic has far more things all competing for its money now than it did even a few years ago. Mobile phones are another obvious yet highly significant example of something that swallows a large amount of teenagers' cash..

The evidence against a qualitative decline in music being the reason for the fall in sales fails to take account of several other factors. The obvious one, which has been discussed here before, is the very common modern habit of "previewing" singles on radio and TV for six weeks or even longer before they're available to buy, leading consumers to be heartily sick of particular songs before they can be bought. (A situation exacerbated by the exponential growth in the number of outlets, eg new music TV channels.)

The reasons for this mystifying behaviour, which has lead to a stupendously predictable collapse in single sales, have often been pondered, but the only one which makes sense is that record companies WANT the single as a format to die. Most singles are not profitable - their physical cost is little less that of an album which sells at 4-5 times the price, and "development" costs have ballooned as the rise of music TV demands ever-more-expensive promo videos etc - and the record companies have loudly bemoaned this fact for at least a decade. There seems little doubt that they WANT single sales to wither and die, because they're basically loss-leaders.

However, as they wither and die, they conveniently affect the headline sales figures of the music business, enabling the companies to cry that their sales are plunging due to piracy, when in fact they're plunging at least in part due to a deliberate and considered policy shift by the companies themselves.

Even leaving aside the proliferation of ever-growing numbers of dreadful reality-TV shite that even the mainstream is tiring of, there are also measureable qualitative declines in the singles market. It's only a few years since the music industry implemented rules decreasing the consumer value of chart-eligible singles (eg you're now not allowed to have more than two b-sides on a CD single and still be eligible for the charts, whereas previously you could have three or more). This is an obvious qualitative downgrade, and could reasonably be expected to affect sales.

Frankly, given these and other factors, it ought to be seen as a miraculous triumph that music sales have held up as well as they have, rather than some sort of terrible criminal disaster requiring a scapegoat. (And that's assuming that the current decline, just two or three years long, IS an ongoing trend rather than one of the industry's regular up-and-down blips.)

While it clearly can't be proved either way, given such reasoning I don't think it's the least bit fanciful or absurd to suggest that the proliferation of filesharing could well have actually slowed this decline (for reasons such as those I outlined in my initial post) rather than being the cause of it.