With most professional societies and private payer groups i.e. Leapfrog Group recommending that every ICU have a board certified intensivist available at all time, there is an expected severe shortage in the future for critical care attendings. In the community, they'll likely be shift work jobs, but in academics it will vary tremendously.
Varies by region also. Here we have a lot of emergency medicine residencies so it's unusual not to find an ER not staffed by graduates of an EM residency (Unless it's a TINY community hospital).
Few states over, without as many residencies, a lot of bigger hospitals are still staffing ED's with mostly Family medicine docs.