Now that the retail Conroe chips are filtering out into the public, I have been planning a new system build. This will be my first overclocking rig, and I have been doing a lot of research into cooling. My question is this: Since the Conroe is a relatively cool-running processor in the first place, is it really worth the extra $100 or so to water-cool it?

These are the factors in consideration, from most important to least:
1. Overclocking Protential: How many more volts, and subsequently more mHz, will water cooling really give me?
2. Maintinence/Usability: How much time will I be spending bleeding or fixingmy water-cooling loop, instead of actually getting to use my computer? Which will be harder to move to the LAN party: A liquid system or a system with a GIANT heatsink?
3. Noise: Which will make more noise: An internally mounted 120mm fan on a monster heatsink, or two 120mm fans on an extrenally mounted heater core?

The specific cooling hardware I was looking at would be something like this:
Big Air: Tuniq Tower 120 (Whenever it becomes available)
Liquid: Swiftech Conroe-Compatible CPU Block, MCP655 Pump, and Single-Pass Double Heatercore

I saw a review in a magazine that even with passive cooling, X6800 can work at full load without a hitch. I suggest you go with a air cooling and save your money to get other wothwhile components. Besides, water cooling maybe troublesome. I'd recommend the Zalman CNP9500. They're very good heatsink and on par with some watercooling system. Sure they maybe expansive, but it's worth it.

A conroe consumes less power than a smithfield or perscott intelc ore so any cooler capiable of overclocking those will do just fine on a 6600. I like the tunic tower but don't know where to get one. I've had good luck with zalman and thermalright so you could check out there solutions. Water cooling is big and requires more attention than a heatsing and fan.

Yeah a good after-market HSF should be ample cooling for that Core 2 chip with overclocking. If you don't mine spending more $$$ then get water-cooling.