Tiki is licensed LGPL, while most projects of this type are GPL.
Tiki has an all-in-one model, Swiss-army-knife approach to features, compared to the small core, add third party modules for completion model. Features are not broken with updates. All the features and languages are in a single download. Tiki is, as far as we know, the open source Web application with the most built-in features. This is inherent to the model.