The difference between the Extension Warehouse and the Extension Store from Sketchucation
The Extension Store from Sketchucation - http://sketchucation.com/resources/pl...
The Extension (Plugin) Store from Sketchucation is a specific bridge which is tied into the Sketchucation Forum and is a link to the plugins which have been uploaded there through the years. It is a way to search the forum from inside of Sketchup.
The Extension Warehouse is a newer feature which is built right into Sketchup and which hosts plugins directly through Trimble. The Extension Warehouse is to plugins, what the 3D Warehouse is to models. Except that all of the plugins hosted through the Warehouse have to pass a test for quality control.
The important thing to remember when getting into Sketchup plugins, is that, for a decade or so, there have been thousands of user coded plugins created for Sketchup. Only recently have the plugins become integrated and searchable from within Sketchup. Before that, they were uploaded and shared over various places on the internet. ANYONE can make a plugin and release it, so there are multiple plugins out that will do the same thing. It is up to the user to experiment with what works best for them.
The user made plugins are the heart of what makes Sketchup so great. The plugins available make working in Sketchup faster and more enjoyable. Just take it slow with learning them and don't download too many at once, so you can have a chance to test the ones you get and then decide if they are worth keeping or not.