The Fire is advertised as a tablet, it is effectively a souped up reader, nothing more or less.
I agree that it appears to be more of a ebook reader, competing more with Nook. Amazon will be coming out with a larger tablet perhaps in time for Xmas which is more competitive, at least size-wize, with tablets. But again, I suspect that which Amazon is offering is much different than what Apple/iPad is offering, so potential buyers should look at these things closely to determine which is will and will not do towards meeting a particular user's desires. [I was shocked at the restrictions Apple put on the iPad, not to imply that the Amazon tablet might not be even more restrictive.]
As to Silk there is one more kudo. You have no control of what amazon is doing with the information they CAN gather while you are suffering the web.
One could make the same complaint of Apple requiring the user to transfer personal docs via the company store application. One could also complain about the censorship Apple applies in terms of not even allowing some political categories of documents to even be sold for the iPad, for example.
Basically, I am saying is look careful at what you are getting for your buck.
Agreed 100% -- they all have restrictions which will grate more or less depending on the needs of a particular user. Also remember to look at the Nook and the Sony eBook readers, which have their own fan bases -- and their own sets of advantages, and restrictions.