I just read again today the claim that you should use + for string concatenation in VB. You should NOT. Just because you can doesn't mean you should. VB has the Concatenation operator & as distinct from the + operator. Yes for the most part adding two strings is the same as concatenating them, but adding two variables is very different from concatenating them... that's why in a dynamic language it is important to have two different operators.
The correct one to use is & for concatenation, and use + for addition. So for strings use &.
See my previous blog entries on this for more details....