Long sales pages convert. There are a few reasons, one is that long pages give you the chance to pre-empt and answer each and every question or concern that the customer might have. The other reason is that merely by spending a long time reading your sales page, that person has made an "investment" (of their time) in what you're offering, and now they want to get something for that investment.

You're right. It is long. Really I wanted to make sure everyone's questions were answered. I figured for those who were interested in buying, they would want to know everything about the product.

Also I wanted to show everything that was in the product, and with all the videos and resources, that takes some space!

Long sales pages are able to present the pain the reader feels, detail the solution they need, provide an offer, establish their authority, highlight customer success stories, counter objections, and reverse risk. (This is all yanked from Sean D'Souza's book, the Brain Audit: http://www.psychotactics.com/the-brain-audit-marketing-strat...)

It would be hard to do all of this with a short sales page.

It's actually true that people respond better to longer sales pages. It's been an internet marketing staple for years.