No, I haven't gone and bought a Lumia; I remain one of the tinfoil hat brigade who go in for the crazy conspiracy theory that Elop will one day jump back to Microsoft, taking the juicy bits of Nokia with him and leaving only a withered corpse of the Finnish giant in his wake, and...

Wait, what? Oh, right.

Well, anyway, a friend of mine does have a Lumia with an AMOLED screen, and I noticed that his only shows the time. I told him about thp's fantastic billboard app which allows all sorts of useful customisations of the low-power standby screen. My friend thought it was interesting & useful, but my google-fu was weak and I couldn't find an equivalent out there for WP/Lumia.

Does anyone know of an equivalent of thp's amazing billboard app for AMOLED Lumia devices?

Hmm, let you friend check that his firmware is up-to-date and also that his settings applications are up-to-date (so that his application are updated in Store).
After that let him go to Settings/Glance and set up what's shown on stand-by screen (notifications and general info).
He could also install from Store Glance Backgrounds application and add wallpaper there.
Not exactly Billboard - but close enough.

Thanks - that's useful. Not Billboard, for sure, but still some customisation options. I don't know WP at all, but I'll tell him to poke around in the Settings and check out the Glance Backgrounds app you mention.