Hey, if you like the game, you like the game.
Depending on what exactly you like about it, here's what you'll find a little more of if you choose to keep playing it:
-More (and more interesting) instanced [http://www.wowwiki.com/Instance] dungeons .Hopefully your server is populated enough for you to find groups to do some of the more beautiful ones, like Shadowfang Keep and my personal old favorite, Maraudon.
-More zones to experience - If you're only a few days into the trial, you might still be in the starting zone, or just outside of it. Although a lot of the game's charm comes from Northrend and Outland, even the old world (Eastern Kingdoms/Kalimdor) have plenty of awesome places, though I'm partial to Stranglethorn Vale.
-More people to meet - I've gotta say, most of the people I know certainly weren't met on my trial account, and even though most people I see I feel indifferent towards, you find the occasional rare gem who's quite a great person.
-More interesting talents and skills - Some of the most interesting abilities that Rogues have come from Talents [http://www.wowwiki.com/Talent] and skills that they get much later on in the game (Cloak of Shadows especially!)
-More (and better!) items and equipment - I cannot stress this enough. Even when you're level capped, there's almost always a piece of gear you can upgrade by PvPing or doing instances, raids, or receiving as a reputation reward. Many quests will end up giving you equipment rewards that you can use, so the more you play, the better gear you get.
Now, I could go on a tangent about how I wish I had the 70 + days played time spent on guitar instead of WoW, or my Calculus grade being higher, or completing every new FPS to come out, or practice for Stepmania, Guitar Hero, Quake 3, or Ikaruga, etc, etc, etc...
But you know, for a long time, I actually enjoyed WoW, and perhaps you won't leave it with as bitter a taste in your mouth as I did.
Honestly, who you play with and how much you play matter the most. If you have friends and you enjoy it together, it's a much better game than the monotonous grind that people say it is.