This one has been bothering me for a while, and it's kind of a two parter.
Mutual Appreciation in specific and the Mumblecore movement in general.
The thing is, the makers of these films are so open and amicable about their processes that it makes it hard to judge them at all. I follow their production blogs and root for them when (inevitable) troubles set in. I admire them as filmmakers who have a vision and stick to it. I just can't get into most of the movies at all. I find it hard to get into a movie with a lack of drama, action or plot. I understand they are going for a 'realistic' dynamic, however just because it's like real life doesn't mean it's interesting.
A friend recommended that I re-watch Mutual Appreciation with an eye towards the underlying meaning of what the people are saying (or more accurately, are stuttering, slurring and, yes, even mumbling). I just couldn't do it though. For me to even begin to care about what may or may not be laying below the surface I have to be interested at least somewhat in the surface. Car chases and boobs are a good start, but really, I would settle for a character that I wouldn't walk away from during a conversation.
I realize that it's probably silly to spend so much time thinking about a rather obscure (to the mainstream, at least) cinematic genre, but hey, someone has to.