In my opinion, you are underestimating the speed difference between SSD and HDD. My MBP boots in under 10 seconds with my SSD, SF-1222 controller. The spinning wheel literally only does a 720°. Done.
All of my apps load practically instantly (XSlimmer also helps). All of my plug-ins within Logic Studio and Reason also load instantly. I have never dropped my laptop, but with a SSD, the worry of losing my data from a impact like that is greatly reduced.
Computer also wakes from sleep in a snap. No spinup.
Who is? I know SSD is amazingly fast but my point still stands, high capacity SSDs are very expensive. Going from 500GB HD which is what most current MBPs have to 128GB SSD sounds ridiculous. 128GB may be enough for some people but I wouldn't take that for my main computer. External HDs aren't that nice with laptops either.
Apple can do what they do now, offer SSD as a BTO for those who want it but I seriously doubt they can force all buyers to live with 128GB or pay hundreds of more for 256GB which is still less than what current MBPs have. Sure there is 512GB but its price is astronomical.
SSDs are definitely the future but the price per GB must come down by a lot before they can fully replace mechanical HDs. Besides, like I said above, SSD is great for OS X and apps but for storing other things it starts to be quite expensive and HD would do the exactly same thing for 1/10 of the price.
I definitely want Apple to bring SSDs to all models because they simply fly but 1) with reasonable price tag 2) without sacrificing the amount of storage. That's why the only way IMO is what I said above, SSD stick + 2.5" HD. You don't need SSD storage for your music, photos, videos etc, those are just fine in an HD.