It may be a seller's market, but it's worth noting that your chances of being hired without going through all of the inane interview processes frequently discussed here are still slim to none at tech giants and hot startups.
The large/hot companies have no problem finding enough candidates to jump through their hoops and, wisely or foolishly, many startups are content to sit on unfilled positions until they find someone they think meets their criteria. So only a subset of sellers have the leverage many think they do.
I agree that "hot" companies have their own localized demand, but I don't think that's reflective of the majority of companies in the tech field who are now being encouraged to imitate these top-tech players hiring practices.
The large/hot companies have no problem finding enough candidates to jump through their hoops and, wisely or foolishly, many startups are content to sit on unfilled positions until they find someone they think meets their criteria. So only a subset of sellers have the leverage many think they do.