Pffft, writing this plugin should take a short amount of time; if it takes any more than 15 minutes in SMF, it's being done wrong.
Wedge on the other hand has to tackle it slightly differently, because their embed code is... um... unusual and I'm not entirely clear why it's being done the way it is. It's still probably 15 minutes but I need to test it to make sure it won't break anything else.
(That's using the basic integration. Using the full on API is naturally more complex.)