First point, fossils are rare. We know this not just because of how infrequently it occurs, but also because of the process.
From encyclopedia.laborlawtalk.com:
Fossilization is a rare occurrence, because natural materials tend to be recycled. In order for an organism to be fossilized, the remains normally need to be covered by sediment as soon as possible, however there are exceptions to this, such as if an organism becomes petrifaction or comes to rest in an anoxic environment such as at the bottom of a lake. There are different types of fossils, and fossilization processes.
So lets build a model from what we can now conclude. Let’s take another animal that has fossilized remains. There have been about 30 t-rex fossils discovered since 1905. Many of them are not considered to be the same species. We can group them into about five different species; T. rex, T. bataar, T. efremovi, T. lancesis, and T. movojilovi. None of the fossils are complete, and no one knows how many bones the t-rex had. Now, T. rex was considered to be a common dinosaur based on the unusually high number of fossils we have for it. Now, whale population has always been much smaller then many other species. To me, it doesn’t seem so absurd to have about 1 ancient whale transition for every 5 t-rex fossils.
I know this isn’t perfect, but we can begin to see where low numbers are very reasonable. Note also that the different species of T-rex that I named are considered to be transitions. Anyway, not all of the information here may be perfect, but I hope we are beginning to put some perspective into the issue that is more then a yeah huh/nuh uh debate. I would appreciate someone with more knowledge then myself also helping to take this in a more productive direction.
Brad