No countries joined the EU in 2008. 10 countries joined in 2004. See the related question below.
Actually, it was in 2004. The following countries joined the EU.CyprusCzech RepublicHungaryEstoniaLatviaLithuaniaMaltaPolandSloveniaSlovakia
Hungary joined the EU in 2004, but has not yet joined the Euro currency.
Bulgaria has not yet joined the Euro zone, it joined the EU in January 2007.
Two countries joined in 1986. They were Spain and Portugal.
Sweden joined the EU in the year of 1995.
No new country joined the EU in 1999.
Finland joined the EU in the 1995.
On the 1st May 2004 Hungary joined the EU (European Union)
Malta joined the European Union on the 1st of May in 2004.
Joined-Up Thinking was created on 2008-10-03.
The United Kingdom joined the Common Market in 1973.
Croatia joined the EU on July 1st, 2013.