Actually...
Iv researched this subject rather extensively -without having to go as far as learning to write track pad driver code, (which I am vary tempted to do) I know what Im talking about.
Here is the situation
1. After 2005, Apple no longer implemented the open source ADB track pad driver for its powerbooks. Instead they implemented a USB track pad driver that is not open source. This new driver is the one that utilizes two finger track pad scrolling.
2. iScroll2, (
http://iscroll2.sourceforge.net/) which implements two finger right clicking, does not support USB track pads because the driver is not open source. iScroll2 only support apple laptops with ADB trackpads. Post 2005 powerbooks have USB track pads, hence, are not supported by iScroll2.
3. Apple has a patent and/or copyright on the implementation of two finger right clicking on there USB track-pads. I don't remember which, Id have to find the E-mail again from Alex Harper, author of Side Track at Raging Menace. (
http://www.ragingmenace.com/)
4. In Alexe's E-mail he explains to me that it would be vary easy for him to implement two finger right clicking into Side Track. However he is hesitant because of Apples legal hold on two finger right clicking.
5. Powerbooks retain there market value VARY well and are still going for over $1500 on ebay. Hence, still a competitor to the Macbooks.
6. Shortly after Apple switched to the USB track-pads, they announced their switch to Intel and the eminent introduction of the Mac pro. The switch to the USB driver is probably coincidental and the patent was probably to protect the two finger scrolling. However, considering Apples notoriously whacky marketing tactics, I wouldn't put it past them to purposely not release two finger right clicking for the previous version of the powerbook. Why develop and test for a platform that your abandoning anyway. Also this small marketing strategy is easy, takes zero development and is a small bragging right to steve jobs on another way to push users to the Macbook pro's. And anyway who's gonna take the time to complain. -Well me personally, Im on spring break now and I have lots of time. Many other 1.67ghz powerbook owners are annoyed by this to.
7. Using Alex as an example, no small third party developer wants to come close to stepping on one of apples patents and become intrenched a life ruining lawsuits. Hence they wont touch the two finger right clicking on the USB track-pads. And considering Apple just implemented two finger right clicking on MBPs, I don't blame them because doing so could easily be construed as competition. Apple has been know to pull some crazy antics in the line of protecting there patents. See
http://blogs.zdnet.com/BTL/?p=3482 if you don't believe me.
8. Contextual menus which are accessed through control clicking are a vary useful and efficient if not necessary to manipulate and navigate your mac. Having to reach over to press the the control key is vary cumbersome and at times impossible to do if your sitting in a certain position and have to move to free up a second hand to press the ctrl button. I constantly have to use contextual menus. I am seriously considering buying an ibook just so I can access them with one hand again without being a contortionist. BTW, I know you could get a wireless three button mouse but who wants to drag that around with you. I despise peripherals on my laptops.
I WOULD ALSO LIKE TO NOTE THAT I LOVE APPLE AND AM NOT TRYING TO TURN ANYONE OFF TO IT. I own a 1.67ghz 15in powerbook and a 60gig iPod and I would lose my sanity without them. To tell you the truth Id rather be running a AMD with Linux GNU... but thats a different topic