Gimme an I, P, T, V...

IMS (and specific hardware) is needed to deliver reliable IPTV and other multimedia services, say the IMS-proponents. IPTV is dead, says Telepocalypse (among others).

Well, if you really want to try stream high-quality multimedia on-demand to the users, then sure, you are going to need a lot of expensive infrastructure to make it into a good user experience. I would agree, that form of IPTV is pretty much dead.
You can just download a torrent of the file and watch it anytime, much easier, cheaper and you can share with your friends too! But somewhat illegal...
That's what scares the distributors and why they want the streaming option. They don't want to let go of the content. So then there's DRM. Typically this is highly restrictive allowing the purchaser to only play the content on specific devices. It irritates the customer. The price is also higher, because you get to own the content.

From a marketing perspective streaming is better for the media companies(telcos etc), it maintains the link with the consumer and enables usage based charging, better market data and possibilities for (time-sensitive) interstitials. I just can't understand why they are making it so hard for themselves!

Why do you need to stream the whole file?
Most of the content can be delivered in the background, ready for use whenever someone wants it. The streamed part just completes the picture. There are any number of algorithms that could be used to 'split' the content. Think layers, movement. What percentage of the content would you have to hold back in order to render the background content sub-standard? Probably around 5%.
So a multimedia supplier could still deliver streamed content(of non-live nature), but, with the reduced bandwidth requirements, you would not need a particularly fast link in order to view it. Perhaps I wouldn't need IMS to deliver a guaranteed bandwidth for 50fps, just 2.5fps! Perhaps I wouldn't need IMS at all...

If this is by any chance a new idea, then it's now public domain, so anyone can do it! (if anyone makes millions on it, then I hope they'll take pity on me and buy some consultancy!)

Here in Thailand, I can buy counterfeit DVDs of all the latest movies for around $2.50, but I don't - because 50-75% of them are atrocious quality, often created by someone with a camcorder in the cinema!
I'd rather pay $10 for something higher quality, but not $30...