Conventional Publishing versus Self Publishing

How many people opt to go through the trouble of finding the right agent to represent them and hope it will lead to a major publishing house taking on their book...

versus...

having your book edited, formatted and printed on your own and doing your best to promote and sell it using your own resources and contacts?

Which one do you believe is right for you and why?

Anymore, it doesn't seem so much like an either/or question. The success of 50 Shades of Grey (despite being on the list of books that the world maybe could have done without), was a case in which traditional publishing followed self-publishing. Increasingly, publishers seem to be looking to buy the reproduction and translation rights for self-published works that are already demonstrating popularity online.