There will be a workshop in Bern on October 19 to prepare datasets - get the details here. To get involved you can suggest a dataset, send us a note OR just sign into the forum and heart this post below if you would like to be involved.
If you can parse the German, I suggest taking a look through presentations from the last Opendata.ch conference, where the hackdays were announced, notably the keynote by Pascal Jenny (@TDkonge) - Wie der Schweizer Bergtourismus von Open Data profitieren kann (PDF), and the Open Tourism & Transport Data track: Christian Trachsel, Christian Helbling, Stefan Keller, and Andreas Liebrich.
A couple of projects on the theme can already be found on the old make.opendata.ch wiki, and there is at least one interesting initiative to check out in the Open Knowledge and School of Data network: the Belgian Open Tourism working group.
See you in Arosa ! Please visit http://tourism.opendata.ch for more information and to sign up.