I'll address a couple things brought up.
Even if you are a Warlock, you will mostly compete with Wizards for loot - for the most part mages will always compete for loot since they all really need similar stats (except master spells of course). Even the new armor sets are listed for wizard/warlock.
Wizards can be tough solo at the start on group mobs but, down the line you get a group encounter root. I have found even if the root breaks and 3 guys charge at you, the group mobs individual enemies are pretty weak and usually you can just stand and kill them before they kill you. Wizards get a few a couple encounter spells and a couple AOE spells (1 including forge of RO that you don't get until lvl 55). Wizards will get the bigger single target nukes and Warlocks will get the better encounter nukes. When deciding I sometimes like to just search for the lvl 55 - 70 fabled spells on broker for that class. Check out what type of spells you will get to use at the top and see if they sound like abilities you would like to have.
(i have a 70 wizard, 18 warlock and 60 conjuror, so most of my info will be on wizzys - i love mages though)
The single target root for wizards has a 15% chance to break when target takes dmg and the encounter one I think has a 20% chance. Sometimes you will just happen to strike that 15% 3 times in a row with constant root breaks. And sometimes i've layed tons of DoT's and still nuked and the root never breaks after taking dmg 10 times. All chance. Also once you get your encounter root as a wizzy, you can double root your enemies if they are that tough. This is how i've easily killed heroics. When the root breaks they are slowed down for 10 seconds or so. With two roots though one is almost always up and its not as hard to keep enemies rooted as some make it out to be.
I have not grouped as a warlock yet but, from grouping as a wizard - I would hold back my encounter DoT's alot. This happens alot more in lower levels but, when the tank is getting aggro - sometimes it seems hes only aggro'ing one target of the mob at once. Cause i've cast an encounter DOT and the other 2 mobs the tank wasn't onto yet, would come running to me cause I dmg'ed them while everyone else is direct damaging the main target. I would think warlocks have even more trouble since they do more dmg than a wizard for a group shot. It's all the same though. A warlock is doing nice (but less direct) dmg to each target in a group so it kinda lowers all the enemies in the mob. While a wizard will just make it so a tank can powerhouse through target after target in a group mob.
Im not sure on warlocks hate debuffs but, wizard has 1 main single target debuff and somewhere down the line, get a spell that upgrades with each level, that decreases threat to the whole encounter. (and its a nice encounter hate debuff, @ 70 mine is like ~1,500 - 1,900 hate decrease on encounter). Wizzys and warlocks just can't go nuts neccesaily on damage and have to stay semi reasonable. Theres no formula or code as to when you start using big nukes, you'll figure out as you play when its too early to nuke for high dmg and when its a good time, without getting aggro in the group.
They are both fun damage powerhouse classes. And I havn't had too much trouble solo'ing my low lvl warlock and solo'ing my wizard was sometimes more efficent than waiting around for a group, traveling to the group, waiting for the group to all meet. Sometimes XP was better if I just got down and did some grinding. They grind quickly, which means more XP and more personal loot to sell. It's not hard to earn yourself a couple plat in a few days by solo grinding if ya need to. Bottom line, not once during my wizard roll did I think - man this class is letting me down, or it could be doing this better. Very pleased and I had a ton of fun rolling a wizard.
You never mentioned this but, if your into some occasional PvP's I think a wizard would by far beat a warlock there. I've seen a totally decked wizard fight a totally decked zerker. Zerker got the wizard down to 1.5 bars of health - then he successes a root. Steps back and basically blows a lvl 70 decked zerker from 100% health to less than 1 bar of health - then finishes him off. If you can learn to master a wizard you're pretty damn powerful and deadly - though this goes with all classes I suppose.
Woo I ramble alot =p. Think I addressed everything I wanted to. Either one, you'll have a good time and feel powerful =) GL and HF
PS. wizards get the spell that teleports them to a safe location (generally the start of) in the zone. It has a 15 min recast time but, if things are really looking like your a dead man - just hit your depart and your saved. That is VERY handy and its what kept my wizard from dieing ALOT less than my conjuror.
Edited, Dec 26th 2006 2:17pm by Dakkotaa