I think you guys are trying to apply real world economic concepts to a completely virtual structure.  Bitcoins have zero value beyond the BTC Network.  Sure they are exchange traded against currencies like the USD, EUR etc, but it is unlikely that BTC would be used as a replacement for those currencies.  Just try and move some of your coins to pay for your electricity bill, with the fees it suddenly kills your $/kWh.

For me, BTC are valuable in an age where information is the commodity that is constantly traded; open an article on Huffington Post and you are exchanging your impression of a diaper ad for an article on Lady Gaga's meat dress.  That paradigm of advertising to support information has a limited life span (my guess is another 4 to 6 years), beyond that information will need to be directly monetized to its audience and a micro payment structure will be required to handle the transactions.  Right now there is not enough infrastructure to make this viable with BTC (we would need many magnitudes more of hashing power) but it will happen down the road.  Remember, BTC are divisible to 8 powers of ten. That is the smallest fraction of a BTC would be 0.00000001.  Maybe this will be called fractional currency expansion?

Mining with FPGAs will allow people to have an interest paying bank in their back pocket for information purchases.

@Haplo,
I totally agree with your description of the debt/interest cycle.  It is important to remember that our current interest rates are practically below inflation, which in China is diluting their currency against their infrastructure.  Isn't the only way out to stop participating?