Good job, I love this. I find that FastCells are less useful these days as iphone 3G are less common. I prefer to design my complex cells in interface builder for ease of maintenance. But it's just personal taste. Otherwise, everything in there should be very useful for almost any app. I suggest you add support for external services, like Facebook for instance (which a lot of projects use).

BTW, I love DictionaryHelper, it definitely saves you a lot of headaches if you work with a JSON api!