The link below is an article about the 308. It may shed a little light on the 308 for you.
Making A Case For The 308 Winchester
If you dont grasp why the 308 is such a popular round it is probably because you have not owned one or at least a good one.
The short answer is that it makes hitting very small targets consistently and long range easy. Its accuracy potential is outstanding as is its consistency (I attribute this to less barrel/throat wear and subsequent consistent performance). The only real draw back is that at really long range in high winds, it has no where near as windage resistant as other calibers. So it is either a more cumbersome caliber or more practice in the wind or both. The point of the 308 (IMHO) is that the barrels last a long long time. This equates to LOTS of trigger time before the barrel cooks. This affords you to become married with your weapon. When you are married with your weapon, good things happen. As far as energy and terminal performance you just have to select the right bullet for the job. There are more good bullets to choose from now then ever.
After you have owned large 7 mags and large 300 mags, and a modest 308 you will "understand".
Hope that helps!