Dell are getting away with the cheap prices by buying components with limited warrantee. We have a 2 year RTB warrantee on ours. Also keep an eye out for the Celerons, they look good for a home user but are not advisable for a work PC.
Totally agree about the Celeron comments. With a PC it's really horses for courses and if you need to do lots of processor-intensive work (like video editing or high graphics gaming) then you need as much power as you can get hold of. On the other hand, if you only need a PC for email, wordprocessing and light duties like that, then there's no point spending more money on a faster system.
I have to comment on your views of Dell's pricing though! Don't want to get into an argument with you, but people should know that the main reason why Dell is cheaper is that they are the World's number one PC supplier, which means that they have incredible buying power when it comes to obtaining components. Also, as you know, Dell only supplies direct, so they don't have to build in a margin for any dealers.
Finally, it would be fair to mention that Dell does offer a wide variety of service types and durations on their PC range. At present, the minimum warranty is 1 year Collect and Return, but they offer different types of service up to 5 years Same Business Day on site warranty. Again this is a matter of horses for courses, and it makes sense for each customer to decide what type of warranty they need. The needs of a home user are quite different from those of a large business customer.
Time to confess that I do actually work for Dell. It's a great company and they make great PCs. I'm not just saying that because I'm slightly biassed. I have worked in the IT industry for a great number of years and have dealt with many different manufacturers. The main thing that has impressed me most about Dell is the sheer quality of components that they build into their PCs.