Now what is Launch Services?
Launch Services is responsible for launching applications, URLs and documents. It knows, which application can handle which kind of data and files, provides the choices for the Finder's "Open with" menu and can return all kind of useful information on a file or bundle.
Now, if an applications is not added to Launch Services database properly, this can have all kinds of negative or weird side effects:
Usually the Finder should add or update new applications in the Launch Services database, but it doesn't always do so. And there's no convenient way I know of to manually update the entry of an application in Launch Services.
So I decided to sit down a couple of minutes and write a tool that achieves exactly this. Once started, all you have to do is select the app(s) whose Launch Services database entry you want to update. It's name is LSRefresh - and it'll help you out with most Launch Services originated problems.