It is. It's not the "Best movie evar!!! OMG!!!".
I have however, warmed up to it more since I initially saw it. It's a very solid action movie, that's incredibly re-watchable. I don't ever get bored watching it, and even when I stumble upon it on TV halfway through or whatever, I'm compelled to see it through to the end. It's only glaring problem I find is that Tom Hardy's version of Max has no charisma or screen presence. Theron's character is a bit one note and bland too. The story is completely forgettable as well. In the character and story department, it's pretty weak. I have grown to enjoy it for what it is though, which is essentially one long, well made action sequence in a visually pleasing style, that only takes very brief moments to breathe, and if that's all it was trying to accomplish, then so be it.
I think I initially gave it a 6/10. I'd bump that up to a 7.5 or an 8 now.