It is absolutely true that everything about 2013 is superior to 2007 for SaaS businesses, with the debatable exception of the amount of competition in any niche/vertical. It is also true that the best time to start a SaaS business for the 2013 market was 2007 (or as earlier as you can push it). You get a head start on the learning curve, which is formidable, even with lots of people generously sharing what they know about customer acquisition, technical topics, etc etc etc. It is virtually impossible to read your way to scalable customer acquisition (or any other very worthwhile business goal). Past the high-basic/low-intermediate level you have to put things into practice in your own business and see how they work out. In 2007, virtually anybody doing that was breaking new ground for the industry. In 2013, only most people doing that will break new ground for the industry. It's ridiculous how much we don't know yet.

2018 is going to be superior to 2013 in pretty much every way, but don't wait until 2018 to start, if you're on the fence about it.