Here is my opinion
regarding 7xxx series CrossFire-
I think it isn't that people are having "so much trouble", I think they're tired of being early adopters. I can't recall of a single GPU launch that wasn't plagued with one problem or another in dual card configurations.
Think about it- if you drop over $1k for a top-end multi-GPU setup, and in the games you play the most there are persistant issues, that'd be frustrating. It's one of the big reasons why I don't do multi-card setups with new architectures. I'd sooner pickup a second or third 5870 than I would run multiple 7xxx series cards in CrossFire. Why? Driver maturity.
My 5870 is freakin' awesome. Sure, performance wise it can't hold a candle to a dual 7900 CrossFire (that performs as it's supposed to) or dual GTX5xx SLi setup, but it works and provides the performance I want with the stability I desire. It's also about two years old now.
I'm very interested in the 7800s. I'd like to snag a 7870 and pass this 5870 on down to somebody else like my little sister or maybe one of my best friend's sons. But with the current condition of AMD's drivers I'll likely not get a 7800 on launch. I'm likely going to wait a couple releases before I purchase. In that time the drivers will have matured offering even greater performance and stability, inventory will have evened out and prices settled. nVidia will have something from the Kepler family out by then, driving prices even lower (or so I hope). Just doesn't make sense to be an early adopter unless you understand the risks.
I know it sucks, but realistically there's no better feedback than when you first launch your product- the sheer number of different hardware configurations and potential problems that arise... you can't get that level of QA testing in any lab. That's why the first months after launch are typically rough.
Anyhow, that's my two cents worth.