Online pirates understand the market better than their legal rivals. The challenge for TV companies is to catch up.

In the battle against online piracy, it’s been a good week for television companies. The US authorities swooped in on a content-hosting giant called Megaupload.com and arrested four of its masterminds.

But the war isn’t over yet, especially not when it comes to television. The geeks will simply get better at bypassing the rules. If companies want to even mitigate the damage then they need to accept that the concept of a domestic TV audience – one governed by top-down TV schedules – is on the way out.

Once upon a time, we watched programmes on “normal TV – channels one to five – or, for the lucky ones, satellite. Homegrown audiences watched homegrown programmes immediately, but had to wait several months for foreign imports. You could record a programme and watch it later, but unless you remembered beforehand, you’d have to wait for the repeat.

About five years ago, that changed. Suddenly TV was available when you wanted it, through software such as Sky Plus, but more importantly via the internet, on legal catch-up sites like iPlayer when possible, or illegally when not. If you’re under 30, “watching online” is as natural as sending a text – it’s simply how the system works.