I support his proposal to enable --skip-broken by default in yum, but wanted to highlight the most likely long-term solution to this problem, which Rahul mentioned too. AutoQA is one of the QA team's major projects. It's a suite of tools and processes to run automated tests of various types on Fedora. Will Woods is the leader of the project. It's already proceeding at a fantastic pace: we're already running several tests daily and pushing the results to a mailing list. If you're a Fedora developer, you may well find it useful to follow the test results sent there.
One of the future aims of AutoQA is to be able to run automatic tests not just daily but every time certain operations happen, whether it's the generation of a Rawhide tree, a set of updates for a stable release, or even the pushing of a single package to any repository. So we hope to be able to automatically test every individual package build pushed to Rawhide or a stable release update tree for sanity - including dependency problems - before accepting the push. That would go a long way towards addressing this kind of problem.
Even though Will's a superhero and AutoQA is already going along at a fantastic pace, more help is always welcome. So if you have some coding knowledge and this sounds like a project that would interest you, please contact Will - either directly at wwoods A T redhat D 0 T com, on IRC as 'wwoods' (he's usually in #fedora-qa), or through the fedora-test-list mailing list.