A good way to keep track of cases is a special update service on the website of the Court. Each application that comes to the Court's registry and is not deemed by the Court's judges to be clearly inadmissible, will be further considered by the Court. One of the first steps in that process is that the state against which the case is lodged, has an opportunity to react. In order to do so a number of documents are sent to that state: the application, the relevant documents, a statement of facts made by the registry, and a series of questions and issues which the state is asked to address. The applicant can then later react to the state's reaction. Each week, the Court puts a list of communicated cases on its website. The most recently published one (last week) can be found here. That latest update for example shows that there is an application on pension entitlements pending against both Serbia and Montenegro, since the facts relate to the time when the two states still formed a single state.
A good way to stay updated on which cases have passed the Court's initial sifting process.