At times quite spectacularly powerful. It manages great emotional weight through image and action (and a majestic organ soundtrack) which doesn't really carry over to idea and dialogue. When not speaking in cod poetic homilies the dialogue is quite stilted and bland. Some jokes about robots feel like they might have actually been written by robots.
The movie aims for great metaphysical depth but never gets beyond a shallow 'the fifth element is love' position.
It splits itself into chunks of incident not all of much interest. The world building first act is unusual perhaps but slight, leaving you to fill in details (commendable but not worth the effort) and laboring over certain plot points in case you didn't catch them the first five times they are mentioned.
The space stuff is more dynamic. A sequence with Matt Damon works. Exciting, driven by real conflict and stakes that makes sense with Damon delivering a real powerhouse performance.
This is also yet another Nolan movie that I've had trouble with the audio/dialogue sound mix making certain moments incomprehensible.