The one thing you have to do is copy your gwt-dev.jar and rename is as gwt-dev-"your os here".jar (gwt-dev-linux.jar, gwt-dev-mac.jar, gwt-dev-windows.jar). This will be fixed in the next version of GEP.
You can simply add the new GWT sdk in Eclipse.Now everything should work for you. Unless you have Gilead, prepare to update lots of jars and add many more.
Since Gilead was giving me problems I figured I should update to the latest version gilead-1.2.3.823
In doing that I also needed to update to the latest version of hibernate-annotations-3.4.0GA and hibernate-3.3.2.GA
In turn spring-2.0.8, spring-dao-2.0.8, spring-hibernate3-2.0.8, spring-jdbc-2.0.8, and spring-mock-2.0.8.
Now that that was done I tried to start up the app and got this error that I've documented here http://groups.google.com/group/google-web-toolkit/browse_thread/thread/ca5722230f14f54e?hl=en#
So I added those files and ran into a slew of ClassNotFoundExceptions that led me to find out there were many dependencies that the new gilead, hibernate, and spring needed, so one by one I added the following dependencies.
beanlib-hibernate-5.0.2beta1
slf4j-log4j12-1.5.8
slf4j-api-1.5.8
javassist-3.8.0.GA
cglib-2.2
jta-1.1
antlr-2.7.7
Once that debacle was over I was up and running GWT 2.0 ms1 below are links to the different jars you will need to download for maven.
gwt-2.0.0-ms1 gilead-1.2.3.823 hibernate-3.3.2.GA beanlib-5.0.2beta1 jboss-serialization-1.0.3.GA trove-2.1.0
mvn install:install-file -DgroupId=com.google.gwt -DartifactId=gwt-servlet -Dversion=2.0.0-ms1 -Dpackaging=jar-Dfile=gwt-servlet.jar
mvn install:install-file -DgroupId=com.google.gwt -DartifactId=gwt-user -Dversion=2.0.0-ms1 -Dpackaging=jar -Dfile=gwt-user.jar
mvn install:install-file -DgroupId=net.sf.gilead -DartifactId=adapter4gwt -Dversion=1.2.3.823 -Dpackaging=jar -Dfile=adapter4gwt-1.2.3.823.jar
mvn install:install-file -DgroupId=net.sf.gilead -DartifactId=adapter-core -Dversion=1.2.3.823 -Dpackaging=jar -Dfile=adapter-core-1.2.3.823.jar
mvn install:install-file -DgroupId=net.sf.gilead -DartifactId=hibernate-util -Dversion=1.2.3.823 -Dpackaging=jar -Dfile=hibernate-util-1.2.3.823.jar
mvn install:install-file -DgroupId=org.hibernate -DartifactId=hibernate -Dversion=3.3.2.GA -Dpackaging=jar -Dfile=hibernate3.jarmvn install:install-file -DgroupId=net.sf.beanlib -DartifactId=beanlib -Dversion=5.0.2beta1 -Dpackaging=jar -Dfile=beanlib-5.0.2beta.jar
mvn install:install-file -DgroupId=net.sf.beanlib -DartifactId=beanlib-hibernate -Dversion=5.0.2beta1 -Dpackaging=jar -Dfile=beanlib-hibernate-5.0.2beta.jar
mvn install:install-file -DgroupId=org.jboss -DartifactId=jboss-serialization -Dversion=1.0.3.GA -Dpackaging=jar -Dfile=jboss-serialization.jar
mvn install:install-file -DgroupId=gnu.trove -DartifactId=trove -Dversion=2.1.0 -Dpackaging=jar -Dfile=trove-2.1.0.jar