Unless I'm mistaken, MacUpdate has nothing to do with updates being posted in a timely or untimely manner, rather it's the developers who lag and leave MU to take the hit.
That makes no difference, as far as I am concerned. MacUpdate should be looking on their own for updates being available. If I can do it (as I have recently done), they can do it.
That's freakin' bizarre!
The cost of the resources that would be required for them to keep track of the thousands of apps they host would put them out of business, and for all their shortcomings, they're too useful to lose.
Searching for updates is not, nor should it be, part of their business; their business is providing a platform for developers who either make good or poor use of it.