Is open source a good alternative for the initial creator?

I'd like to ask the original designers of Gallery and others :

Let's consider Application-X. A lot of people use it. Its not that great, but its the only application with any market share that satisfies a particular need.

I can make my own version of Application-X that should be much better. I have unique experience and ideas to use in solving the need.

I can :
1) Make much of the application, demo it, seek funding, start a business, hire people for sales/support/development/etc, retire in 5 years a billionaire.

2) Design UML and other docs for the application, release it as an open source project, begin development, see where it goes...

Also, assume that this product is only of use to businesses. Individuals would have little need for it. The product would have to be proven to be accepted by larger businesses.

THE QUESTION : Am *I* better off with option 2 (the open-source project) ?

If I begin work on this as an open-source project, I, like so many others, give away unique expertise and a lot of effort for free. If the application ends up being widely used (i.e. Tomcat, JBoss, Gallery), will I end up with anything other than a resume bullet and a lot of "how do I install" emails?

I don't think I'd ask this question if the application were something an individual would use.

Opinions appreciated.

Thanks!