Unless things have changed then its a different model (well gnunet was initially file sharing but does more now) Our core issues are
1: Self authentication (can you login/create account to the network at your own discretion)
2: Self encryption - Are files encrypted in a manner to allow de-duplication
3: Autonomous network (is the network able to handle all rules itself without any human intervention or authority)
In addition the self validating PKI component is important and more recently the internal currency / token safecoin as this allows for some pretty advanced features and security later on. IF we can get the micr (very micro) payemnts going then each user can micro pay to PUT and then we get to remove another manger groups account transfer data (Maid managers).
So similar in some ways and no reason to really say competing, but potentially very similar goals in terms of security etc. but I feel the core is privacy security and freedom for all the worlds people and that means no web of trust, no human interference at all. So we have taken a different route and at the very core implemented the 3 areas above.
I don’t have the time to compare projects in any great detail, as you will see for very smart people on this forum MaidSafe is pretty complex, imagine doing that every time people ask about differences, it is very hard. So I hope this brief helps and maybe gnunet folks can point out their core objectives and capabilities as that may be a quicker way to compare. Best outcome is projects get to know each others strengths and cherry pick good bits to improve their own project.