SE has always been firm about balance between versions, and not usign anything that gives more advantage over others. WIth the PS3 version, there will be a limit to addons.
PArasersare not completly accurate. You cna run 3 parsers and get 3 different numbers. THe battle system and fights are also different. IF you want to have an idea of your own damage to improve yourself, then fine, as long as you realize the parser is a ruff idea, most can visually see damage they are doing and realize what stats are helping more.
Then again DPS is not the only aspect. FOr BLm's, THMS, and other dps, constint high DPS is bad. You will have more duties then spamming spells at a mob. A better hate meter is more of a benifit then a parser.
If you are going to use some random parser to spam your DPS in a party situation, then you will probably annoy more people then having any benifit. Especially if you were not paying attention to the fight grabbed hate and whiped the party. Heavy DPS classes can do that easily. BLM's can grab hate in 2-3 casts. So it's tiem to back off.
Currently, a player with large sums of gil and the ability to meld IV materia, will out parse the adverage player. But said materia will actually mean you need to watch damage even more. HAndy for the tank, not so much for casters and other dps that can't afford to grab to much attention.
Other MMO battle system don't have such an easy hate grabbing ability.