Dakar. It's hot. Lots of goats. In 2-5 years, it could be a major tech hub -- sooner with some policy and infrastructure changes, but the core is there, from VC4Africa hosting meetups at co-working/social change hubs like JokkoLabs to a budding online community of drupal hackers. The infrastructure seems to remain a daunting challenge, with mobile internet lagging behind, banks not being innovative, and a fragile power system reliant on imported oil.
I spent just under two weeks working with Ashoka fellow Hamadou Tidiane SY, who was elected in 2009 to the News and Knowledge program of the fellowship. He has grown Ouestaf, a small independent news site to almost a household word in francophone Africa through amazing dedication to professionalism in journalistic standards and solid coverage of core issues, avoiding sensationalism. News and Knowledge director Keith Hammonds has a blog post on the model.
How to Build a News Website in Seven Days