I like the idea of a base line tech tree, that you can research "short bow" "claymores" "large axes" "crossbows" etc.
Or in another branch perhaps "copper, bronze, steel"
Off of those tech trees could be the random techs, that modify their base components. "range increase for short bows" combined with a lucky "speciatly short bow training center" for example might have you utilizing a short bow long after your oponents are working x-bows, and never having to work on the more advanced tech.
On the other hand, just because your opponent has these uber short bowmen at the moment, there would be plenty of options to counter him. Researching tower shields and tight formations could yield a unit that can hold their own against the bowmen. If you don't have the resources to build tower shields there would always be the potential for a magical solution. Warp wood, missile immunity, wall of air, invisibility, things like that.
Just because your opponent has a particularly sharp pair of sisors, doesn't mean your rocks won't still smash them.
So as long as we can research fundametals to be able to function in a rock paper sissor environment, I think the idea of spiking the tech tree with hidden surprises that you get randomly as you are researching the base tech they are tied to is a fun idea.
Lastly, while I like the idea of fixed base techs, I'd like to see the tech requirements to unlock various things made random, and hidden. Obviously you need a bowman, a pikeman, and a horseman available from the beginning (or whatever the rock paper sisors basic is). But what you have to have teched out in order to unlock x-bows could be varried, and random. Thus maintaining that "exploration" of the tech tree we all had the first time we played civ 4 indefinately. As long as anything you'd *need* to function is selectable, the rest could be tied in down the line in random orders. From what they are saying there will be a *very* long beta.
Seeing as this is the direction I suspect they are going with it, I thought I'd make a list of what I think are fundamental techs that you need to be able to research. (I think the random bonuses should just appear as researchable once you've met the req's, kinda out of the blue. and let you research them or not as you see fit. You should always know what you are going to get from the tech you are currently working on IMO. or at least a general idea, like you had in master of orion)
So here is my list of inalienable techs.
Food, Population Growth, research, income, magic producing structures (If there are any), metalurgy, defensive structures, fancy racial techs, animal husbandry, and the 3+ basic military unit types (as long as you can build a counter to anything that can be fielded).
All of these should be researchable in their basic forms, in a reasonably predictable linear fashion. Should they figure out how to make nickled bronze along the metalurgy route, that could be a cool side tech that can be totally random and would give a great boost when it showed itself. But you aren't going to race down the tech tree to get nickled bronze because of how uber it is to dominate your enemies in the short game. Just a cool thing that shows up and you alter your strategy to make use of it.
A tech tree like this would result in "what would help me the most now?" out of the available techs. Rather than "what is my formula for teching?"
Lastly, if wonders (or w/e) were based off the randomly placed techs (that are always present) it would further prevent the forced tech choices just to be competitive.