I'm guessing youre one of those people that believe ram is what speeds up a device and makes it run better LOL. Try playing dungeon defenders on your phone and then tell me if its plenty fast enough. Of course TB has a faster processor. Hell the droid x and 2 have a faster processor except they were released MONTHS AGO. HTC just upgraded technology that's already dead, and for some reason youre trying to defend it. I definitely would not want to own this phone with this kind of iPhonish fanbase.
Actually, RAM does speed up a device and makes it run better. Case in point, my dad's pc. It's an older Compaq with a sempron 2GHz cpu & 256 mB of RAM. It was slow as hell. He had to wait around 10 minutes after pressing the power button to open anything. Solitaire took 30 seconds to load, web browser took around a minute. The specs showed it had 4 memory slots with a total capacity of 4GB. I recently installed 2GB (2 sticks) of RAM and it's a night and day difference. Now don't tell me "That's a PC, this is a smartphone." They are both computing devices and as such operate on the same principals. Think of the cpu as the motor and the RAM as the fuel. With more RAM, or fuel, you can run longer before running out of memory. With better RAM (like going from DDR to DDR2 or 3) you increase speed, just like adding a higher octane fuel. There's a reason why faster cpus require better memory. If you don't believe what I have said is sound, try removing half of the RAM from your computer and see how it runs.
As far as the dual core = better battery life, that has to do with electronics theory, specifically energy loss due to heat dissipation and efficiency (resistance). Saying having one core running at 700 MHz is worse than two cores each doing 350 MHz will result in better battery life is valid only if each core of the dual core is more efficient than that of the single core. If not it will lose energy in the form of heat dissipation.
Another issue is how much does each type use at idle. If a single core uses x amount of power on idle, the amount of power a dual core will be greater than a single at idle, because you have two 1GHz cores instead of one, again unless each core is more efficient than that of the single core. So you may very well be using more power on idle with a dual core but less with heavy use compared to a single core.
An analogy is you have a 30 ton load to transport. Two semis will have less of a load on each than if a single semi tried to haul it, but now you are fueling two devices. The only way this is a better scenario is if the two semis get a better average mpg (ie power consumption) than a single semi. Granted, mechanically the two semis will lessen the the strain to haul the total load than if it were hauled by a single semi (which is analagous to heat over time breaking down the material in the chips causing a mechanical/parts failure).
Another would be you have one bulb hooked up to a power source. If you add a second in parallel, each light is dimmer and it puts more of a load (draws more current) on the power source. Now you're using more power than originaly but possibly getting more light than with a single bulb. If you switch to bulbs that are more efficient, you can get the same amount of light while drawing less power. But that's the kicker, in the dual core each device must be more efficient than the single core they are replacing. The PC industry ran into this when they switched to dual core. Some manufacturers where taking two existing single cores and putting them together. It had more processing power, but drew more power and generated more heat.
There are certain laws which cannot be overcome. Energy cannot be created or destroyed, only converted, in this case into heat. If you can lessen the amount of resistance the energy must travel through to accomplish it's task, you get higher output with the same or less power consumtion. It's basic electronics.
So basically what it boils down to is, is each core of the Tegra 2 more efficient than a single core snapdragon, hummingbird, or OMAP? If so then power consumtion and heat dissipation will be reduced for a comparable task. If not then it will still the have higher processing power threshold, but will have the same or worse power consumption and heat dissipation for a comparable task.