Surely these new screens with non-integer multiples of 50Hz aren't going to be very nice for PAL viewing - or is there some fiendish plan afoot to get the whole world on to the same frequency? Multiples of 120 are, after all, potentially rather good for film as well as yankee TV.

"or is there some fiendish plan afoot to get the whole world on to the same frequency"

The choice of 50Hz in the UK with PAL is based on the frequency of the mains supply, getting the world to adopt 60HZ will be quite a challenge !

Historically, absolutely - though it's more political than technical now. Screens long ago lost their physical dependence on mains frequency. I can remember using a 50Hz monitor, but thankfully haven't had to for years.

But because TV in this country is always shackled by backwards compatibility and politics*, there will likely always be a 50Hz root, and that will suck when resampled to a non-integer multiple.

* Without said shackles, digital should have been done as multiplexed UDP-like streams per programme (yes, per programme), and the licence fee should have been replaced by a subscription, but those are other rants for other days.