This kind of thread is exactly why I work at http://linkup.com/ - which is a job search engine that works by only including jobs found on company websites. Let me give a quick example of what that means:
The technology behind LinkUp takes a lot more work than your standard scrape because many companies make it difficult to get to a reusable link to an individual job, and there's no unified format to tell title from description from location. And right now we only have a hair over 20,000 companies, so I don't tell anyone that we're the only site a jobseeker should use - just the first;-)
It is possible for Indeed and SimplyHired to have job listings that link directly to the company's website, the company just has to provide the feeds that those two aggregators then index. (Us, for example: http://www.indeed.com/jobs?as_cmp=ReminderMedia) Your solution puts the trouble of formatting the data on your shoulders while they're offloading it to the companies themselves. I dig it.
That's a great idea. Here's a suggestion for an extra feature: let me group search results by company. Then I can quickly get an idea for who's hiring without paging though hundreds of results.
That idea is actually implemented - unfortunately you need to login to see it. Once you login (which supports OAuth & OpenID), under settings you can turn on the "Group By Company" feature.
Yes, it isn't intuitive. We're overhauling the search results and in the next release, slated for mid-June, these kinds of things won't be so buried.
Twitter has 34 job openings (http://twitter.com/positions.html). They, being Twitter, don't have a hard time finding people so their jobs aren't on CareerBuilder/Monster (http://jobsearch.monster.com/Search.aspx?brd=1&cn=Twitte...). The other job aggregators, like Indeed or SimplyHired, only have the jobs that have been copied onto other sites (http://www.indeed.com/jobs?as_cmp=Twitter - note the links don't actually go to the company website). We (LinkUp) have all their jobs - http://www.linkup.com/results.php#c=Twitter. Another HN-worthy list is http://www.linkup.com/lists/Y_Combinator_Startups, but you'll have to guess what the link is...
The technology behind LinkUp takes a lot more work than your standard scrape because many companies make it difficult to get to a reusable link to an individual job, and there's no unified format to tell title from description from location. And right now we only have a hair over 20,000 companies, so I don't tell anyone that we're the only site a jobseeker should use - just the first;-)