For these two particular tours (firstedit, firsteditve) we will be delivering them post-registration, when you are sent back to the page you were on pre-signup. The goal here is to test providing nearly all first-time editors a guided tour, and to try a version of GettingStarted suggestions where we don't force everyone through Special:GettingStarted right after signup. Users will be given a choice of either taking a tour of how to edit the current page (if allowed), or taking a GettingStarted suggested task. We're hoping to launch that as an A/B test against the current GettingStarted experience as a control, probably next week. 

Already we know guided tours work for new editors accepting a GettingStarted task,[1] and we're hoping it will have similar positive effects for the many new users who don't accept a GettingStarted suggestion, typically because they signed up with a page to edit already in mind.   

1. "Among the users who viewed a GettingStarted article and were given a guided tour, we found a statistically significant 3.9% difference in the rate of first edits made, and an even larger 13.6% increase in the rate at which new users attempted to edit."  https://meta.wikimedia.org/wiki/Research:OB3