Two-weapon fighting is unchanged.
Grapple is...
simpler, but not necessarily
better. (
For a given value of "simpler.") The process is better, but the math is still horribly skewed; if you aren't expressly built for grappling (full BAB, high strength, high dex, devoting all available feats to combat maneuver abilities), you're still fucked over if something with Improved Grab hits you.
Example: To grapple you, a
behir (CR 8) must hit your Combat Maneuver Defense (10+BAB+str+dex+2 if you have Improved Grapple) with his grapple attack modifier of +22. Assuming that the old PHB2 guidelines for equipment and stats are still reasonably accurate, we can expect a 10th level fighter to have a dex of 14, a strength of 18 (including
gauntlets of ogre power +2), and thus a CMD of 28. The behir will successfully grapple you on a d20 roll of 6 or more. (8 or more if you have Improved Grapple.) In order to escape from the behir, you must beat it's CMD of 29 with either an Escape Artist check or a grapple check; the grapple check would be a modifier of your BAB + your strength (+14 in the case of our aforementioned fighter.) Improved Grapple does not improve your check to escape from a grapple. (Escape Artist would provide him with a modifier of +15, less any armor check penalty, if he had full ranks and it was somehow a class skill for him.) Thus, on a 15 or more, the fighter can escape from the behir, who may attempt to grapple him again for free the next time he hits.
Note that this is for a fighter, who is a front-line combatant and who is supposed to be in melee with the behir. If this was, heaven forbid, somebody who wasn't a full-BAB class (a rogue or cleric, for example), they'd probably be right fucked.