How to set up an efficient watch on publications in planetary science?
There are different ways of keeping up to date that come to my mind:


Using your favourite article indexing database listing articles in your field (e.g. Scopus for life/biological sciences or Web of Science). Most databases allow you to set up 'Search Alerts', when results of a certain search string change. This can be done either via E-mail or RSS feed. Usually you can customize how often you get notified about such changes (daily/weekly summaries)
Some citation management programs automatically notify you of recommended and related articles depending on your own collection of articles. For me, this often not only includes the newest research but also older classics and other highly related articles that might not necessarily be very recent.
Thirdly, you can follow your peers on twitter and be notified of their most recent works that way. With the advantage of being able to start off discussions.