I have an old friend who is in Admissions at a very selective college. Just caught up last week after a few years of little/no contact. A big change in the Applications content in ECs these days are that many many kids are Liston companies that they started. I guess the internet is making it easier. to put together a company even if you are a teenager. Also, a lot more internships with businesses and internships with professors at some college or other. Those activities were rare not long ago. Now they are becoming common.
The big deal used to be community service or time spent in depressed areas or countries.