I'm in the same boat! Just about to install and enable as we need to trigger email to customer when they submit a profile from WordPress...
From initial testing it seems to work fine with 4.7.3 however I have only used the "Add to group" trigger and "send email" function. Both seem to work fine.
CiviRules is working on a live site now and performing well. Only have 10 rules which just send emails when people are added to groups. The delayed actions also work fine.
So to get it installed on 4.7.x, simply edit the "info.xml" file for the extension, adding
<ver>4.7</ver> under the
/extension/compatibility element and then installing as normal.
This is by no means a comprehensive test! Please perform your own prior to a live release!