there could well be a long-term power issue to consider with solid state meory as well as the fact that solid state is transient if you want the high speed of access
Slightly over-generalizing, no computer will ever take more power than your lightbulbs, water heater, etc. If you don't replace all your light bulbs with CFs and turn them all off relgiously when you're not in the room, if you don't always dry your wash off-peak, then don't worry about your computer. It spends most of its life waiting for you to press the next key.
I deal with "SSD is really important" fanatics all the time. I do believe SSD will win out very soon, but right now I do two things: provide said fanatico with a second battery, and book said fanatico onto flights with seat power.
I personally believe that the battle isn't between SSD and HD, but between SSD and fuel cells. When you can recharge a notebook in 2 minutes, who cares what the battery life is? People think they are concerned about battery life, but actually they are concerned about recharge/tether time.