All the propagation prediction programs we are used to - IONCAP, VOACAP and their cousins - are based on historical understanding of propagation. They make predictions based on solar parameters and their authors quite honestly explain that their results are monthly averages, rather than predictions that reflect what you can expect today or tomorrow.
ViewProp is something new. It bases its reporting on what is happening today, on paths between your QTH and locations of interest around the world. It does this by drawing on the Reverse Beacon Network's array of hundreds of Skimmers worldwide to keep track of what is being spotted by Skimmers in your vicinity, as well as what stations in your vicinity are being spotted anywhere else. The result is a dynamic portrait of propagation from your QTH to and from wherever in the world, which bands are open and how well.
In addition to showing you a map display of the paths being reported, and on what bands, ViewProp also charts the level of activity on different bands over the course of each day in a readily-understandable format. There's much more to it, too, as you can learn by reading the Wiki with more details and a few screenshots here.
I believe this is the first truly revolutionary use of the capabilities of the RBN to promote understanding of your HF propagation. Try it, and tell us if you agree. The only thing that Rick asks is that you join the Viewprop Yahoo group at this address, and then you can download the beta version from the group's Files section.
Try it, and tell him what you like, what you don't, and what you think should be added. I promise you, he is listening.