A number of points people seem to be ignoring:

1. Regarding faster cpus: higher clock rate does not necessarily equal higher power drain. Mobile cpus, including ARM-based ones, are designed to underclock themselves when they aren't doing anything. A 1Ghz cpu will spend very little of its time at 1GHz. Ignoring other differences that affect power usage, a faster cpu will finish tasks faster, thus being able to return to a lower power level sooner, resulting, in most cases, the same net power usage as a slower chip. Obviously, if the cpu is going to be run at a constant full speed for a while, then it will drain more power. Most of the time, however, that is not the case.

Also, the screen is by far the biggest power drain, especially as LCD.

2. The screen resolution of Nexus One & co and what it means for other devices:

Yes, its true that the Nexus One doesn't have a true 800x480 display. That does not, however, mean that all AMOLED screens have to have the crappy, dithering-esque pixel layout.

3. AMOLED vs. LCD vs. SAMOLED: LCD uses much more power because of an always-on backlight. AMOLED is crap in sunlight, but does true black (my Samsung Impression agrees). Also a dark UI will use even less power on AMOLED, because black pixels use no power at all. Super AMOLED takes the benefits of AMOLED and adds sunlight usability. I'm not entirely sure how much of an effect on power usage the "Super" has, but once again, black pixel = no power usage, dark, but not black, pixel = low power usage. Finally, a visual comparison, with linky for more stuff:

Sunlight (left to right: SAMOLED, AMOLED, LCD):


Indoors (LCD, AMOLED, SAMOLED):