As the title says, I would find it very useful if you could be so sweet and add this tool for apprentice ranks. The reason is that it saves time if you want to find out what blockid you used before, instead of having to look it up online each time. I also find that the /vi never works when setting data id, Im not sure if its a bug or on purpose, but I'd love if possible that this could be added so I don't have to go over with the //replace command so much :)
I generally keep http://www.minecraftinfo.com/idlist.htm open as I build if I'm using w.e. because it has all the blocks and their ids. If you need a block just use control + f it doesn't take very long to find anything.
Hit f3+h and block IDs will be shown when hovering over blocks. For /vi I believe you need to use /perf mm
Thanks, I don't think the F3+h shows placed blocks though, such as ids for the supersmooth sandstone slabs, mushroom blocks and proper id for placed stairs, slabs and such. Its ok though, I can still figure it out from id lists and such.