If you are faced with two technologies, ideas, or frameworks - how do you compare which has a wider body of knowledge? Specifically - can you tell if X does NOT have a wide body of knowledge?

Here's something I think will NOT work for this: Google fight.

Example: Dataset Vs. ORM

Do the results mean that datasets have a wider body of knowledge?  not really. they (probably) show that more people posted about problems they were having getting datasets to work.

Maybe it means "wider body of problems"?

maybe not. For example: NUnit vs. JUnit. JUnit clearly wins, and I am pretty sure it's not because it has more problems but because it has been around longer. so it MIGHT hold true that there is a wide body of knowledge there. but with NUnit having over 1 million results, can't it be said that they BOTH have a wide body of knowledge?

so how do you decide if something has a body of knowledge and is worth pursuing?