I think the Euro will survive because I think the ECB will start buying Euro governments' debts. Whether all the countries within Europe remain within that group is an interesting question. Arguably allowing Greece in has lowered the bar for entry since Greece has a very different set up to say Germany (i.e. low tax collection, lots of low level bribery to smooth the business flow and a very laid back approach to certain economic principles)
Whether the UK embraces the Euro one day or not will largely be at the behest of the UK based banks (and to an odd extent so it should be - I'll explain if queried :) ) What will happen though is Britain will either advance or decline relative to Europe based upon our leaders in business, education and in the government and vice versa. The European project is actually a good thing; benefits can be seen as: reduce wars, unify currency, unify legislation - i.e. level the playing field in effect. Just like the Roman Empire, The Federation of the United States, the British Empire etc.. a single set of ruling institutions is normally hugely beneficial for all those who survived the fight to get there and who didn't allow themselves to be made slaves (Romano Britain was much superior in many ways to anything else until the Renaissance period and even then was still a great model.) The great thing about the Euro project is it hasn't been done by war but that's also its achilles heal, without war there isn't the dominace required to force people to comply (and so actually benefit by compliance!)
For Europe and the Euro to succeed rapidly it will require a rapid transfer of sovereignty to Brussels, its as simple as that. The longer they take the more painful it will be and the slower the benefits. In the short term it looks like the UK benefits from being outside the turmoil but the reality is it would have been great if we'd taken the lead in this project and applied some good anglo-saxon principles and common sense to the whole process. As it is when and if we fully join the new state of Europe it will be a larger Germany rather than a larger Europe.
Once Europe is united then we'll need to work on adding the US...!