There are RPG fans in the world who love the volume of options and strategy one gets from turn based combat. Then there are the gamers who despise sifting through menus to select actions and curse the names of role playing games that stick to this tradition. Both play mechanics have strengths and weaknesses to keep in mind, but at the end of the day, which wins the battle?
In the Red Corner...
Real Time combat comes out swinging. You hit a button to attack and press a direction to move. Fights are typically quick and visceral. Keeping battles exciting should be a major concern for RPG developers because, for the most part, the combat is the game play. Whatever the story may be, whatever the quests may have you do, it's all just a big excuse to make you run around and kill monsters. Real Time combat has the advantage of immediacy over its Turn Based opponent. You're always an active participant, never simply an observer.
On the down side, most RPGs involve a party of characters, and any character not directly controlled by the player is controlled by the computer. Computer guided characters are idiots. Even tweaking their behavior with a chain of commands in the menu may not guarantee these AI morons will avoid committing suicide, using ineffective attacks, or wasting their magic points and precious items. Another problem with Real Time combat in RPGs is the tendency to promote button mashing. It can be too easy to just stick with one effective attack or combo for most of the game.
In the Blue Corner...
Turn Based Combat avoids the idiot AI syndrome by giving the player absolute control over all character actions. This results in the player controlling a small army in Strategy RPGs with ease. It's also possible to incorporate many more attack and defense choices, positioning, and tactics into the slower paced Turn Based fights. Unfortunately, the slow nature of Turn Based combat also results in many encounters becoming drawn out affairs.
Turn Based combat can incorporate much more cerebral fare into its play mechanics, but after the fiftieth encounter with a slime, many gamers just want to kill the damn thing as fast as possible and move on. Also, battles in all RPGs tend to be repetitive. This leads to the Turn Based version of button mashing. Why try to figure out if the flame elemental is weak to water or ice if attacking with the really big sword proves just as effective? There's no point in having a dozen menus full of options when you don't need half of them.
The final count...
In conclusion, which method wins out? This referee has to call it a draw. There are very good reasons to pick one approach over the other. It all depends on the developer's goal: Action or control? Immediacy or intricacy? Heck, this gamer will happily play all of the above. All I ask is that developers make the most of their choices and give us a good clean fight.