There is a new trend shown by established blogging site and web based service providing companies. They are coming up with Job Boards.
Common feature between all of them is that they are following Web2.0 rituals like they are using ajax technologies, they are categorizing jobs and providing RSS feeds of their contents based on that categories, they are also providing widgets for their contents and finally they are also charging for posting of jobs.
TechCrunch a very good blog site which keeps track of new technologies, web services and web launches also has job board called CrunchBoard. They have a benefit of very high user base which reads their blog daily.
Check out here : http://www.crunchboard.com/
GigaOm which has blogs by Om Malik and associates on various technologies and web services. Few days ago they also launched Job Board targeting hi-tech professionals.
Check out here : http://jobs.gigaom.com/
37Signals which has many state of the art web based applications has recently launched job board. They are targeting designers, programmers and tech savvy people.
Check out here : http://jobs.37signals.com/jobs
If you constantly looks out for new jobs for you and/or your friends or like to see(or analyze) changing demands of professionals, technology or criteria then you must subscribe to feeds of these job boards.