Its a Buggy World (and here are some examples)
Check your math! The scaling mana regeneration glyph info is incorrect (0.06 X 18 does not equal 1.20, it equals 1.08) The bottom outer turrent on the red side (and probably some other ones too) is not working correctly, it sometimes will not target champs who are attacking friendly champs, and sometimes will not attack champs in range without minions (I've noticed it with Caitlin) and also sometimes will not attack champs in it's range with you. ARAM 2v2? I had a reset ARAM game where only 2 people on each team got connected, one of the persons who didn't connect was in a party with someone who did connect and they were really confused because it was not their fault. WRONG SCREEN! Sometimes the champion select screen doesn't show up for one person when they are in a party, and the screen that shows up. Is the screen before you enter que (where it shows everyone in the party) this happened once for me and once for a friend. These are the only bugs I've noticed recently but I'll keep an eye out for more. :D