Even with Java 7 Update 6 build 19, Introspector.getBeanInfo() performance appears to have regressed substantially with Java 7:

The attached sample program produced:
D:\Java\jdk1.6.0_32\bin\java.exe ResourceBundlePerfBug took: 18 ms
D:\Java\jdk1.7.0_04\bin\java.exe ResourceBundlePerfBug took: 46 ms
D:\Java\jdk1.7.0_06\bin\java.exe ResourceBundlePerfBug took: 39 ms
 
So Update 6 improved things, but 39ms is still a substantial regression from 18ms.