Although it's obvious and usual that newer or, the latest versions, consume more resources and CPU power, it is noticeable on a mediocre older system that Maple 13 is slower than Maple 12. This point is merely for interest sake only and maybe for Maplesoft to take a look into their code to see if they can improve it's performance.
The character typing test on both versions show Maple 13 falling behind faster than in Maple 12. ie the lag time in typing increases more quickly with maple 13, suggesting that the distance to get the character to print on the screen has increased (more code, routines or whatever it may be that maple has to jump through to get a character to screen).
Dual core, dual processor machines won't notice this or machines greater than a P4 1.7 desktops as I have concluded in a similar thread regarding cpu performace.
In any case one should not expect any increase in typing time between any version regardless of how new or old they are. It's possible that Maple is jumping through routines it should not need to, to print a character. Now this has nothing to do with the more important operations Maple does with Mathematics, but it doesn't mean you should overlook some of the more simpler aspects of the program.