I have finished "Exorbitant Privilege" (the dollar book) by
Eichengreen. The author is a former IMF advisor, btw. He is a
(somewhat) conservative technocrat with all the attendant attitudes. He
does proficient job at describing the subject. Towards the end of the
book he analyzes the future of the dollar as world's reserve and
contract settlement currency and its potential replacement. Naturally,
I have a certain stake in dollar's well-being so this subject is of
less than academic concern.  He discusses several candidates. He says
that Euro does not have a unified central bank (and the book is
written before the recent Greek troubles) and the member states have
diverging interests. The preceding discussion, as to how for decades
European countries unsuccessfully tried to keep their exchange rates
synchronized, was convincing.

Eichengreen does mention that the countries on the fringes of Europe
(say Russia) are using Euro for settling contracts because they trade
with the European countries. So, Euro is likely to become a regional
currency.

Eichengreen then talks about renminbi. Well, for one, it is not a
freely convertible currency, does not have a developed financial
market, infrastructure and, thus, liquidity so if has a way to go, if
China ever decides to move in this direction, before renminbi can
challenge the dollar.

Eichengreen then discusses more exotic alternatives.

- IMF's special drawing rights (SDRs) - this one is for governments
  only and no non-governmental trading is allowed. Besides IMF is
  sort-of owned by the US.

- Baskets of currencies: its own problems depending on which currency
  to include.

- Gold. Eichengreen says that banks lately do not like to own gold
  because, surprisingly, it lacks liquidity: you need to sell it to
  get the right kind of money. IMF was having trouble selling 200 tons
  of gold recently.

- Timber. Some fancy school, Harvard(?), was buying forests in
  places with its endowment money. They got burned once they
  needed cash quickly.

So, it is not that the dollar is all that great, it is that there is
not an immediate viable alternative. With his technocratic approach,
and since he is not radical, the reading is a bit dry. You don't get
the feeling that you are reading this secret knowledge that nobody
gets (that you do when you read marxists or lefties in general).

Eichengreen concludes, rationally if a bit predictably, that it is not
the exchange rates and fancy monetary schemes but the economic and
political power of the country that stands behind it, that ultimately
determines the strength and acceptance of a currency. Somebody, pass me
Ritalin.