The great online community around Tableau is one of Tableau's key benefits for me, and I think Tableau can do more to tap into this on a product level and really use this as a competitive advantage. I'd like to offer 3 examples below.
For Tableau 11, there is talk of going beyond the "show me" tab with prebuilt templates and machine learning recommendations. I think that would be a really useful place to tap into the vast Tableau community - adding a few basic mechanisms like keyword tagging, voting on templates, comments, searching, browsing would go a long way. For example, as a user of Tableau Desktop I would love to be able to my own templates to Tableau's library, and search (from within the product, not on a seperate website) for "customer profitability analysis", "sales rep performance analysis", "finance waterfall analaysis", ... and see what common practice templates have been made available in the community. One click of the button would then load that template for me, and allow me to link it to my own data sources.
A comparable community-driven mechanism for public data sources would also be great, when we want to search for public data sources on things like exchange rates, demographic data, commodity prices, accident statistics, sports scores, ... The key words here for me are ease of discovery and ease of use. Embedding such a public data source list within Tableau Desktop should improve over simply googling for such a data source by relying on the community - there should be some type of usage count or voting system that allows me to see which census data source most people have been using, and hopefully some type of comments from the authors but also from other users. And again loading the available data source into my viz should be one click of a button.
For both templates and data sources I think there is potential in not only having free templates / free public data sources, but also for-pay templates and for-pay data sources offered by other companies via Tableau's platform. Essentially a Tableau App Store and Tableau Data Store. Making templates available for-pay would be tricky because people could trivially copy the viz mechanics, so some type of protection mechanism would be required - but still, something to think about?