This is an "I told you so" letter from Amazon to it's naysayers, in no uncertain terms. Marketplace, Prime, and AWS were all "bold bet[s] at first, and sensible people worried (often!) that they could not work." Jeff highlights each of them in detail. This is a longer-than-usual letter, coming in at 5 pages.
The third time is a charm. First came Amazon Auctions, which morphed into zShops, which transformed into Marketplace. And now accounts for more than 2 billion units sold.
Making Prime happen required retooling of inventory processes and fufillment centers, including the acquision of Kiva. If you're not famaliar with Kiva, it's pretty cool - robot shelves! But all of this ultimately paid off. FCs expanded from 15 when Prime launched to 109. Prime Instant Video was added in 2011 and Fulfillment by Amazon was included. In 2014, 71% of FBA merchants said they saw 20%+ increase in unit sales after joining FBA, but as a customer that just makes sense. Why would I order from some place else via Amazon, when I can get it via Prime?
Amazon Web Services
AWS has a nice customer list including Pinterest, Dropbox, and Airbnb and is starting to add large enterprises that are seeing the benefits. AWS has more than a million active customers. AWS also has a strong leadership position in the cloud market right now.