Bugs
some red stone stuff disappear and Xray the world some seconds
windows 7 lag minecraft more than windows xp does
big worlds killing my game so i always run void world even flat world is llagy
when whater spill like from block to block it lags me even when i place whater itself in one place
some mobs are realy lagy
i know this stuff in my work like in creating maps in minecraft
i cant run big worlds or windows 7 only if im using video options mod