What significantly improved accessibility via integration?

Apple integrating podcast support into iTunes

While the technical capability for syndication was established around 2003, the leap from niche hobby to mainstream medium required a dramatic increase in consumer accessibility. This leap occurred when Apple made the decision to build comprehensive podcast directory and subscription functionality directly into iTunes. Because millions of computer users already had iTunes installed, this move created the most significant platform invention from the consumer's perspective. It offered a massive, familiar, and trusted portal for discovering and listening to content, thereby eliminating the necessity for early adopters to download and manage separate, potentially unstable, aggregator software such as iPodder.