How to 'stay up to date' in your field? In academia, it's important to stay up to date with the latest 'hot' hypotheses in the your field. By 'hot', I mean the hypothesis that are most important/topical/relevant/popular. Perhaps the best way of staying up to date in a given field is by reading the literature. But  I'm wondering if there are any shortcuts? Are there any websites or papers that list the current most 'hot' hypotheses in each field? Google Scholar lists the most cited papers but I'm wondering if any resource goes one step further by listing topics?
I suggest some ways of becoming up to date:


Following the related top scientists and authors on that field on Google Scholar 
Following the related top researchers and professors web sites and their research lab and groups publications.
Ask to contribute to work for or work with them.
Check related Linked-In groups to know more about academia and industry.
Visit their labs and talk with them.
Take part in the related conferences.
Check the related conference proceedings. For example, the IEEE web site has lots options to help you.