Comment by teej

It's about level of interactivity, responsiveness, and robustness. Shiny web front-ends to a relational database just don't compete on the same level as desktop workhorses. Mint, Gmail, and Freshbooks are nice web "applications", but their innovation is in solving simple problems with incredible interfaces. The innovation in Textmate, and Photoshop is that they enable a high amount of manipulation and automation that simply can't be delivered over the web at this time.