Evilore said something I thought was important about power armor - I think it should have mystique, and this mystique is built upon by seeing NPCs (like brotherhood of the steel) walking around with it earlier in the game. If you tried to take these dudes on, you'd get smoked. I remember that very thing happening in Fallout 1 via random encounters. You should see it, be terrified, and have the idea in your head that maybe one day you'll get a suit of your own. FO3 never quite got it right, Power Armor just felt like slightly bulkier regular armor. I like what I'm seeing of how power armor is handled in 4 just in terms of its appearance and mechanics.
Incidentally, if I recall Fallout 2 made it quite easy to get lots of power armor (if I recall you could just run down the map at the start of the game and pick some up, if you knew where to go, but even besides that, there was lots).