User blog comment:Kirkburn/Technical Update: August 17, 2016/@comment-5558012-20160818005729/@comment-126761-20160818123137

The banner shouldn't get any larger than shown on that example - additional appreciations are hidden until you expand it (and the same appreciations won't show on multiple page views). Multiple people can appreciate a single edit. It covers all namespaces.

Discovering how popular this kind of feature can be is really part of the experiment - it could be wildly popular, or it could be very subdued. Seeing how it behaves in the real world will help us decide what could work in the future. (And we'll likely make tweaks to the prototype during the test.)