Even Chris Wallace of Fox News has taken to challenging Paul Ryan for specifics on Romney's policies. Ryan had a lot of specifics in his budget that the Republican House passed two years in a row. Romney has disavowed everything in the budget he had previously called "marvelous". Ryan claims to have details but it would "take too long to explain", so you'll just have to take his word for it.
The constant refrain from the right is that there is a clear choice between Obama and Romney, something that Ryan says in every other sentence. A complete lack of detail is not how you characterize the word "clear", it would be more like "fuzzy", "indistinct" and "misleading".