I have a friend who contracts for Ford in their mechanic's training division. About the only issue the Focus has faced are issues with defective ball joints. I don't have a Focus, but do have a 1998 ZX2. In nearly 5 years, I've only put 40,000 miles on it because it's just my commuter car. However, through the whole time that I've owned it, I've averaged 28-29 MPG (city and highway driving combined.) The car has been great, reliable and dependable. I was looking to trade it for a newer Focus because I'd like to have 4 doors on my vehicle because my daughter is getting bigger. About the only thing that the standard Focus didn't have was the Zetec engine like my ZX2 has. I thought they were using the Zetec engines across the whole Focus platform, but I guess I was wrong. The Focus that I test drove was a bit quieter than my ZX2 - but I suspect that's because the Zetec engine will rev higher.
Overall, the Focus seems like a good car. I don't think I'd purchase a new one because of how much they'd depreciate. Buy a "nearly new" one where someone else has eaten a big chunk of the depreciation.