I like to think that it's almost guaranteed that we will venture beyond our solar system - it might take hundreds or years (or maybe thousands) but, in one form or another, we'll get there.
[I suspect that transporting big lumps of meat about probably isn't the way ahead - travelling in an uploaded form seems far more likely (e.g. Greg Egan's Diaspora).]
That we're going to solve the energy crisis, and that this era isn't a brief spike in human population, burning at breakneck speed through the very finite 'windfall' of exploiting found reserves of fossil fuels seems unlikely.
But we now know there's more to mankind than Rome.
haven't i already beat the odds of being born amoung the 93 billion who lived before today?
As usual, mankind's biggest problems arise from our inability to scale social interaction well, not from technical prowess (or lack thereof).