I've never dated an ENTP but I have been 'charmed' by a few (they are good that at :P)
The Ne/Ne dynamic is CRAZY. My experience of this primarily comes from a 2 and half year relationship with another ENFP. There is definitely never a dull moment when Ne is in the drivers seat. My only concern would be complete 'burn-out.' This is what happened with my ENFP and I; we were both too 'head in the clouds' and jumping all over the place - we both needed some kind of anchor and gounding, neither of which either of us could provide the other. Having said this, this was during my early 20s. I would imagine that two mature/healthier Ne-doms would be able to find a way to manage this aspect of the relationship.
Personally, I find myself prone to clashing with both Ti and Fe. I'm not trying to wage a war against users of these functions; I just find that I have to be more wary when it comes to certain types of discussion/conversation. My biggest issues are with Fe, and seeing as this is the tertiary function for ENTPs - I doubt this would be a huge problem (unlike it is with Fe-doms and I, eek) By the way - I'm not typist! I'm just stating that I do tend to have difficulties linked to Fi v Fe clash!
ENTPs do crack me up though. They are so much fun to hang with. I wouldn't date according to MBT; however, the older I get, the more I look for a partner who can help me keep my feet on the ground (as well as letting me spend 80% of my time- head in clouds, with the faeries XD)
I'm such a rambler >.<