Looks like we can't reproduce the issue or there's a problem in the test case provided.
Ext GWT Premium Member
FieldLabel and Alignment
Internet Explorer 8
Windows 7, 64 bit
GXT 3.0.2 Shapshot (9/19/2012)
If I throw a GWT Label (or HTML) widget into the field label, alignment doesn't work correctly. It is a little bit higher than the label.
Does GXT have a different approach for putting read-only values into the value fields for a Form? In any case, I would hope that GXT's FormLabel would play nicely with the native GWT components.
Screenshot is from IE8 with developer mode use to select surrounding Div to show the alignment issue. Based on font/label width/etc. it can be more apparent in other situations.
Quick change to FormsExample.java replacing email TextField with a Label.
Label emailLabel = new Label("firstname.lastname@example.org");
TextField email = new TextField();
p.add(new FieldLabel(emailLabel, "Email"), new VerticalLayoutData(1, -1));