New Bitcoins are created at a predictable and fixed rate, which means that as more and more miners join the network the more difficult it becomes to get a slice of the block rewards pie.
sounds like a good recipe for boom and bust cycles, but instead of repeating what I just wrote, please read my latest blog entries @earthcustodians, check out
From Gold To Fiat And Cryptocurrencies, And The Fate Of Irrational Exuberance
Bitcoin & The Manic Bullishness Of The Crowds Struck Again (WAM/Jeff Berwick Talk Cryptocurrencies)
The Problem With Power VS The Zero-Sum Game Economy
and more