BuddyPress.org

I am a very conventional idiot. I seriously doubt I will ever be in a position to afford a custom code.

What are the perils of choosing open source scripts for main projects?

How long these projects like wordpress will be in good shape with continuous updates?

I heard Automattic is profitable. But what if the leading developers loose interest and leave?
(Tumblr has overtaken WordPress for having more blogs on the web)

How safe will we be then?

Is it wise to choose such a plug in like buddypress for a bread and butter project?