Well, my opinion according to file and project wizards, that they don't clearly correspond to Eclipse UI part (http://wiki.eclipse.org/User_Interface_Guidelines#Wizards).

1) First of all when we open any of our wizards, for example, JSP File wizard, we see Next validation message: Attribute Name must be set (screenshot-1). According to Eclipse UI user should see something like this: Create a new JSP file.

2) Now begin to print some name in corresponding field -> Result: there is no any validation message (screenshot-2). According to Eclipse UI user should see default message: Create a new JSP file, if the file name doesn't equal to exist page in project.

From other aspects there are OK. You can exam Eclipse UI behavior of wizards, for example, using standard JSP wizard or wizard for folders' creating.