Cydia is by saurik who is a member of the dev team.
However the updates are from the sources generally which are 3rd party repositories. I think it is just a case of the twilight zone between Christmas and New Years so not many people doing work.
I have a similar problem, I guess... Cydia doesn't update when I open it, I always have to hit refresh to see new packages. It hasn't bothered me enough to try to find a solution yet. Anyone else experience this?
I came across this page because with 6.1 it has a similar issue. the packages did not install correctly due to too much traffic from the new jailbreak release. The fix for my packages not updating seemed simple enough. After Opening cydia click on the Changes tab at the bottom center and then click refresh on the top left. this downloaded and updated all of my packages.