I think its wiser for it to be on the main menu not buried within the search sub-menu. I actually wanted it to be ctrl & click to take you to the definition like in netbeans and eclipse but couldn't get it to work properly.
The reason is because its one of those methods that is incredibly helpful when exploring a new code library, you can quickly bounce about the links reading the code as if its a book, following a function here, a class there. If you bury it in a sub-menu then it wont flow as smoothly from one place to the next. (this is also the reason I put my shortcut right at the top of the right click menu, so you dont have to move the mouse)
On the other hand however, you could argue why use the mouse at all? When you have the F4 key could do use the keyboard for everything.
I dont know the correct answer but from using right click to quickly go to definition in visual studio and ctrl click in eclipse/netbeans I feel the less amount of clicks made the better

Mike