....The combat is better... Define better. World of Warcraft has you right clicking the mob, and pressing a few keys now and again. Age of Conan has you actively pressing the keys. Which is better? I prefer Age of Conan's - it makes me feel like I'm not just sitting there pressing a couple of keys while my characters makes a couple of different attack moves.
...the characters and armor look cooler... Define cooler. World of Warcraft is a high fantasy game, with multiple races, lots of colour, over-the-top concepts. Age of Conan is grittier, low fantasy, a lot more realistic. Characters in World of Warcraft are simple, deformed, and common. Characters in Age of Conan are realistic, proportionate, all human, and varied. Armour in World of Warcraft is over-the-top, cartoony at best, the height of high-fantasy. Armour in Age of Conan is based on realistic concepts, gritty, but not lacking in flair, design or quality.
At the end of the day no game is "better" than the other as a simple truth. It's all subjective. It depends on what you like. I do like high-med fantasy, but I also am attracted to low fantasy feel.
I do enjoy World of Warcraft's openness, and that's probably the one thing that World of Warcraft banks a lot of it's success on. Not the only, but a large aspect.
Problem with Conan is that the areas feel very disjointed. In FFXI, in order to get from Bastok to San d'Oria, I'd have to go into South Gustaberg -> North Gustaberg -> Konschtat Highlands -> Valkurm Dunes -> La Theine Plateau -> West Ronfaure -> San d'Oria.
Now, that's still zoned, you pass through an invisible barrier, a short loading screen, and there you are in the next zone - but you actually had to travel through different places to get around. With Conan I can easily click on an NPC and travel half the kingdom in a few seconds.
What I would say, however, is not to judge Age of Conan too harshly just yet. You know that World of Warcraft is an older MMO, not ancient by any means, but...old. It's had time to correct it's mistakes, to change it's way. And Age of Conan will do that in time.
If you can't stand bugs etc, then I'd say put AoC on the shelf for a few months and let them sort out the bugs (the same sorts of bugs that plagued WoW from the start and took many months for them to sort it out) and then see.
But at the end of day, it's all subjective. Look at the different sides, look at each point and at the end of the day, try it out. Don't let fanboyism, or bias affect your decision because you could end up missing out on the most amazing moments of your life.