As was suggested above, you are seeing a "mutation," so to speak. The plant isn't really turning into an X-man, though. A better term would be abnormal growth (read: not harmful growth).
These plants grow so repeatedly and during the spring and early summer relatively quickly. As such, this type of thing pops up periodically. Similarly, DIonaea are prone to false vivapary, dual headed traps, etc.
In a nutshell: it's something weird and neat on an already weird and neat plant. Great growing! The plant looks awesome to me, by the way.