A nice one liner which lists which grub version is installed on which partition (Source)

In addtion there exists a nice PythonScript findgub from McDaniel. It displays much mor info than the one liner below. In general the one line is sufficient. 
The oneliner doesn't work on my Mint 13 system any more. Another tool bootinfoscript works perfect for me.
fdisk -l 2>/dev/null | egrep "Disk /|/dev/" | sed "s#^/dev/#Part /dev/#" \
| awk '{print $2}' | sed 's/://' \
| xargs -n1 -IX sudo sh -c "hexdump -v -s 0x80 -n 2 -e '2/1 \"%x\" \"\\n\"' X \
| xargs -n1 -IY sh -c \"case \"Y\" in '48b4') echo X: GRUB 2 v1.96 ;; 'aa75' \
| '5272') echo X: GRUB Legacy ;; '7c3c') \
echo X: GRUB 2 v1.97 or higher ;; *) echo X: No GRUB Y ;; esac\""
Unfortunately this doesn't work any more for grub2. But there exists a tool called bootinfoscript which detects grub2.