Reminds me of the old school-oriented games of yesteryear. I could see this being useful for those learning to type, if they resist the urge to look at the keyboard. Apparently, I have a tendency to type "F" when going for "G".
A few things I would note:
-when two of the same letter tanks are on screen it seems to go for the one closest the direction you are already facing rather than the nearest to your tank, which threw me off
-when two close riding tanks come from the top, the letter of the bottom tank is covered and you can't see it until the top tank is shot, which also threw me off a little bit
-also, accuracy has two c's
Other than that, for a simple keyboard aid, it is FREAT!