Your "today" options can push their way into Amazon's market, and eliminate the unnecessary Amazon step...
Wal-mart is certainly trying to do just that. Amazon had to drop their the minimum order value for free shipping back down when Wal-mart took the offensive.
As far as I'm concerned, Amazon is already imploding. Their search engine has become nearly useless, returning whatever the hell it wants, rather than what you searched for. It keeps getting worse, not better. Have you compared the item counts when you sort by Relevance versus Price Low to High? Where did they disappear to? What the hell is wrong with their site?
I used to place thousands of orders from Amazon every year, now I'm down to dozens, just occasionally checking them before buying a large ticket item to see if they've got an incredible price on it. And even then I only go through and buy from Amazon when nothing leads me to believe it might be a scam / counterfeit / mislabeled / etc.