Everytime I see the increasing Beta numbers, it doesn't really bother me. I'm used to it, being a pretty avid X-Plane user. Its very common to see upwards of 20 betas come out for each X-Plane patch, not too mention normally two or three scraps of the release candidate.
Not too many people ever complain to hard about the bugs in X-Plane. They're always there, and there are always new ones. Over time though, things get fixed.
Then again, each version of X-Plane will see maybe twenty full patchs, whereas we're on what, number two for LO-MAC? At least we haven't waited as lang as for HL2.