Any claim that a class sucks is usually off the mark in terms of addressing real issues with the class. Granted, it can have some valueable feedback contained within, but this is usually overshadowed by emotion and exaggerated or skewed claims. Mages have many valueable assests and abilities as a class and still make up a fundamental class of this game.
However, they do have some legitimate issues and I will attempt to describe some of them here. I would honestly hope that your enjoyment of the game and class is not derived solely on opinions from others, mine included.
Some primary concerns:
-Damage scaling at the high-end game is inconsistent between melee classes and caster classes. This lends to the perception that 60+ casters have difficulty competing with melee classes, particularly in a PvP environment. We are looking to address this through continued itemization for casters as well as other methods.
-Spell-resistance gear is prevalent and helps other classes to mitigate damage against spells. Conversely, casters do not have a comprable way to mitigate damage. Again, this is something that scales inconsistently and can be seen more clearly in 60+ competition. A tentative approach may be to review distribution of resistances on all items. Another consideration is the game mechanic of "spell penetration" which could be summed up in the notion of countering resists. Many options are being reviewed and I may have more specifics for you later on this.
-The lack of changes to the mage class after many patches have left many mages feeling neglected while at the same time illustrates another discrepancy. As the game has developed around them, mages have had to apply a consistent class in comparison to altered classes. While adjustments are being made to assist the mage and other casters and mages will have a talent review, some are unhappy with the imbalance now and are prefering to play another class until mages are revamped. The upside of this being, if you are at the end of the balancing reviews, expect changes to put you at the proper level of the "new" playing field. In short, this means, overall, more buffs and fewer nerfs. And the last shall be first...or however that goes.
The bottom line is, if it's fun you should play it. That is the fundamental return of a game. Fun is an experience, not something that can be translated through text. Try it and see