It's Sunday morning and I'm still drinking the coffee, so I'll throw in $0.02 USD. Y'all are forgetting the golden rule of capitalism - make more money. RIM makes zero money beyond the initial sale of the device, and by that I mean OS upgrades are free (i.e. no continuing return on investment). Let's not target RIM here, Nokia is the same exact way - the two companies have extrememly similar business models (the difference of course being RIM with BES, and Nokia with their telco hardware/etc.). Then add in how the US cellphone market's hands are handcuffed by the carriers, the major source of revenue for them (and in RIM's case, nearly the only one outside the government) who determine what features are in what device based on *their* revenue model, not what the consumer wants (hello, T-Mobile and Sprint).
You can rant and rave all you want about "too fast!" with devices, but the reality is that they need to keep making new handsets with different features to sell to different people to make money. The trick is to re-use the same manufacturing processes under the hood to keep production costs down and gain a higher profit margin (such as the same CPUs and board design, same RF parts, IC designs, etc.) Again, Nokia does the *exact* same thing -- have you looked at the plethora of N-series and E-series devices, not to mention all the S40-based ones as well? Same hardware (within reason), different shell and OS features.
Your days of yore are gone forever, buying a device and expecting it to be current for more than 6 months - tops - is a pipe dream. The market moves fast and hard and the device manufacturers have to keep up, selling highend devices to early adopters (which is the segment with the most disposable income and are willing to buy their devices). We on this forum are in that bunch, of course - I keep a device for just about 6 months before rotating to a new one (some longer, some shorter). There's always improvements that I'm after that are never "upgradeable" to an older device, which is of course planned obsolescence (e.g. the fact that an "older" S60 device running "S60 9.1" can't be upgraded to run "S60 9.1 FP2" because Nokia doesn't want it to, they want you to run out and buy the new device instead so they make more money).
/end diatribe about capitalism.