Top 3 observations:
- Deeper reach - global
- Compressed cycle to list and begin recruiting process
- More transparent activity for viewing other hiring trends at competition
Keep in mind that job postings are just that, posted jobs. They require people to be looking and see the posting and then respond. It's not active or proactive recruiting, it's passive.
Technology allows all of the things above, as it alerts people to opportunities with alarms/filters set to ping them when a job is posted that matches their presets, but interested, engaged, and qualified respondents need to act to make the technology useful. There will always be a need for a seasoned recruiter to connect top candidates (that may not be actively looking) with top positions.