It is my understanding that all of the BTC scalability problems can be solved with relatively uncontroversial updates:
1. 10^15 units -> Protocol can be updated so that satoshi is no longer the smallest unit. No one should disagree to this.
2. Block size -> Older spent transactions can be deleted PLUS today the chain is being spammed with fee less transactions - once we have just 1/10000 part fees most of that will be taken care of.
3. 51% attacks -> Client will likely be updated with an IP-filter at some point and then people can quickly filter out disruptive players, maybe even propagating their block-list through the network.
I think my BTC value prediction for 2012 is already failing, the value is rising TOO rapidly! Of course it might be a bubble or slow down again...
(Glad I bought a bunch at 5.06)
Anyways I'm long so it's fine.