In the end, it really makes no different. See it like this: You got a phone and new models on a regulair basis. What will happen is this. Apps will come out. Probably 99% will work just fine for atleast 1 or 2 years. Sure it might run faster on the newer models, but it will still work fine on your. Only exception being games but who buys a phone based on games?
The other case would be where you have 1 model each year. In that year 100% of the apps will work. After that 1 year you will get apps that will only work with the new model.
So at the end of the day you end up with pretty much the exact same situation. For me, that 1% or less apps that might not run on my phone after 3 to 6 months is such a low amount I couldnt care less. I rather have the advantage of always being able to buy the best specs out there unlike having to wait 1 year for a new model. The other big disadvantage of that is price. 1 model a year means you can keep prices high. With regulair newer and better models the price of the older, but still capable of running pretty much everything, models will get lower.
Just compare the iPhone with other phones. Buying a iPhone is like getting ripped off but being happy about it.
Are you sure?
The 3GS was the second phone to get a Cortex-A8. Hardware wise they're pretty sound. Sure it's not 1Ghz but is there a difference, besides games?
Which brings us back to the subject matter. If games are not the determinator for phone purchases then why do you want constantly new hardware on the curve? It's even more pointless I'd argue.
And the mobile world doesn't move that fast, actually. Not too sure why the 3GS didn't have a nHD/WVGA screen, but other than that it is pretty much on par with what a flagship phone should be even till now (Moto Droid, Palm Pre Plus, HTC's Snapdragons, Xperia X10 etc).
Now if they lag 1 year behind the first dual core A9 on Android/WP7 then you have a valid point. Right now I can't really see it. I'm for less phones per year, less depreciation means it's possible to get an iPhone for 600SGD under contract and trade it in for 300-400SGD value if you want to get a new one next year.
Right now my HTC Magic in comparison has gone to 150SGD trade-in with my initial 550 off-contract purchase. Of course it's better not tied up to the devil but still, the Magic is/was a 300-400SGD purchase on contract.