For one month my job is to maintain a client-server application in VB5. I has not been the most fun thing in my life, but at least it provides some occupation. Quick pros and cons of VB5 :

Pros

Easy interface designing

Keyword With enhances readability for multiples operations on an object

Very well integrated debugging

Cons

Fixed layout, resizing must be handled manually

No always well-suited events

Poor string handling capabilities

Poor readability due to default properties

No inheritance

Random crashes of the IDE

Deployment hell (why a simple demo app, with no dependencies doesn't run on others 'puters?)

No 'Inc' function (this function is one of the first I used proudly in Basic)

Overall it has not been a bad experience, and it leads to a little wishlist for Java.

Syntactic Sugar

A 'With' keyword

Behavioural change

A true static resource oriented user interface definition. Two years and a half ago I designed my own based on XML. The performances were quite acceptable, there is so much resource used with Swing that you can add many IO and parsing before you feel the overhead. I don't know how it would perform today (proprietary source code, and I don't work there anymore). Of course it depends very much on the graphic toolkit you use (AWT, Swing, SWT, QtJava, Java/GTK, dog.gui...), that's probably why there are multiple ways to do it (serialization, LUXOR, code generation...) and no one really as clean as a good ol' resource file compiled.