I read some interesting "claims" about steel frames vs aluminum frames over at another website (I'll try to provide link)

Pretty much stating what I have roughly understood before. Steel fails very gradually, but aluminum fails precipitously. Anyway they had a pretty interesting discussion about how aluminum fatigues. I'll try to dig it up.

http://www.cyclingforums.com/t54788-.html (below quote taken from post #7)

"Aluminum is different from steel in that it does not have a fatigue limit. That means that any time there is any stress in the material, it gets closer to failure. Steel has a fatigure limit, where if the stress does not exceed this limit, the material will have, for all intents and purposes, an infinite lifespan."

Comments please.