Apache Tomcat 7 was just recently announced – or more specifically, Tomcat 7.0.0.
Apache Tomcat 7 is the first release of the 7.x series, and thus the Apache Group does not recommend adopting it for business use yet. The code changes that went into Tomcat 7 are so extensive that they would like to have some real-world (but not production) testing first.
Tomcat 7 is the first version to support Servlet 3.0, JSP 2.2 and Expression Language (EL) 2.2.
Java SE 6 is required to run Tomcat 7, but the JDK is not needed; since Tomcat 5.5, only the JRE is required as Tomcat comes bundled with the Eclipse JDT Java compiler to compile JSPs.
I just hope that adoption of Tomcat 7 does not follow the pattern of KDE; KDE 4.0 was roundly taken up by all major KDE platforms in spite of the warnings given by the KDE team. Yet, I expect Tomcat 7 to be more reliable than KDE 4 was.