This is definitely not the case. As of December 2004, 12 of the 25 EU member nations have converted to the Euro. These countries are Austria, Belgium, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal, and Spain. Additionally, several countries who used currencies replaced by the euro have adopted it as their standard. San Marino, Monaco, and Vatican City have done so with explicit agreement of EU member nations; Andorra, Montenegro, and Kosovo have done so without such agreement. Ten countries recently joined in 2004, and are expected to adopt the euro in a relatively short period of time: Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia. However, the remaining two countries, UK and Sweden, seem to have no intention of changing currencies, at least for the foreseeable future. UK has an opt-out agreement, so they have no obligation to convert. Sweden, however, does not have an agreement, and ostensibly it must at some point accept the euro as its currency. (credit to mister_c for UK correction, thanks!)

An update. Jan 1, 2007 the first post-Communist country made a switch to the Euro. I think it's the smallest of these countries and also the farthest west and farthest away from Moscow. Slovenia. In CZ, HU, PL and SLovakia, I don't think it's even scheduled for 2008. By the way, welcome Romania and Bulgaria! Thry just joined Jan. 1st 2007.

As of 20/10/07 at least two of the major countries have not. Britain still uses the pound and Sweden still uses the Swedish Krone.

No. "The euro (currency sign: €; banking code: EUR) is the official currency of the Eurozone (also known as the Euro Area or the Euro Land), which consists of 13 European states (Austria, Belgium, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Slovenia, and Spain) and will extend to include Cyprus and Malta from 1 January 2008. It is the single currency for more than 320 million Europeans. Including areas using currencies pegged to the euro, the euro directly affects more than 480 million people worldwide. With more than €610 billion in circulation as of December 2006 (equivalent to US$802 billion at the exchange rates at the time), the euro is the currency with the highest combined value of cash in circulation in the world, having surpassed the U.S. dollar." "While all European Union (EU) member states are eligible to join if they comply with certain monetary requirements, not all EU members have chosen to adopt the currency. All nations that have joined the EU since the 1993 implementation of the Maastricht Treaty have pledged to adopt the euro in due course. Maastricht obliged current members to join the euro; however, the United Kingdom and Denmark negotiated exemptions from that requirement for themselves.[4] Sweden turned down the euro in a 2003 referendum, and has circumvented the requirement to join the euro area by not meeting the membership criteria. On the other hand, several small European states (The Vatican, Monaco, and San Marino), although not EU members, have adopted the euro due to currency unions with member states. Andorra, Montenegro, and Kosovo have adopted the euro unilaterally, while not being EU members as well." Source and further information: http://en.wikipedia.org/wiki/Euro