Service, application or feature?

I'm doing quite a bit of research on IMS at the moment. Apart from the head-spinning array of acronyms, one of the things that jumps out at me is how differently the IP and mobile worlds treat "things that people can do with their phone & the network".

There seem to be three main schools of thought:

- "It's a service" - which means "we, your carrier, will install a bunch of complex kit, maybe customise your end device, and bill you for using this thing every time/month/per-byte/etc. We might also try & charge you for using someone else's service, and bill you on their behalf."

- "It's an application" - which means "we, your carrier, will try and sell you some software that makes this thing work, and maybe even host it for you. However, you will 'own' it, which means that any problems are yours to solve"

- "It's a feature" - "we, your carrier, are annoyed that Microsoft / Symbian / someone else has bundled this in with the software of the phone, and that it connects to some server outside our control, relegating us to the role of 'bit pipe', without any chance to earn extra revenues, even if we're adding no appreciable extra value".

There's also the fourth school of thought, which is "It's bait for out community/advertisers/OS, and if it's not good enough, we'll keep adding extra bits until it is". Which translates as "we, Google / Microsoft / Yahoo / eBay will gladly give you a whole bunch of stuff for free, because we know it's actually pretty cheap to provide, even though you value it quite highly"

It strikes me that one of the things that IMS will enable is much simpler service vs. application vs. feature arbitrage. Of course, this isn't the IMS intention at all, which is purely about services - but to make IMS work, it seems likely that phones (and networks) will need such a lot of upgrade in terms of "smartness" and performance, that the feature & application stuff will probably sneak in regardless.