Update:Further combat improvements
Following Saturdays update the combat system has been tweaked further. The retreating was still too difficult (particularly when being attacked by multiple players/monsters at once) so this has been improved and made easier.
The "keep 3 best items" rule has also been modified. If you attack another player then you now lose the item-protection for 20 minutes of game time! This makes the player killing aspect of the game more dangerous and exciting, but it also increases your potential reward, as if you kill someone else without item-protection you can now get the best loot! People without item-protection have a small skull drawn above them.
After many requests the guards in Varrock city now attempt to stop people fighting. There are large number of guards at the bank, so assuming they haven't all been killed you can now withdraw your money more safely.