Thought Experiment Time: What if Rome never fell?

[Xyzse]

8. What is known as the Dark Ages, I don't think was really dark

It was just a period of intense commercial activity.

http://listverse.com/2008/06/09/top-10-reasons-the-dark-ages-were-not-dark/

If Rome did not fall, we would probably still have gladiatorial combat rather than football.
Slavery would still exist.

It would still probably be the same as now. Actually no, I think it may be even worse.

Rome as a society had a very fixed method of thinking. To advance, such things has to topple so that new ideas and systems can be considered.

They did provide some sort of stability, but it would probably be inching along more than anything else.
With their method of appeasement of the masses, they kept their vast majority dumb and illiterate to maintain their power.

At some point, consider an empire a monopoly, which at the beginning advances civilization till it stagnates. If Rome continued, they would be trying to hold on to power for too long and advances would have been stifled.