People always read way too much into this.
At the end of the day Dell is a retailer. They want the best solutions available to maximise profit opportunities with their customers. Obviously Intel has been giving them a competitive deal on CPUs and now (quite some time ago actually) AMD met the same price or bettered it. The fact that AMD is becoming more marketable thanks to it's performance benefits over the past couple of years only helps the situation.
I'm sure AMD priced their proposition profitably as they don't really have the capacity to run a loss-leader through Dell to gain mass-market awareness. Likewise, Intel can probably now increase their price to Dell as they are no longer the exclusive suppliers.
This gives the customer choice which is a good thing as it also means that the consumer should also now research a little and self-educate. This will mean that Dell customers can probably not now but in the future make a fairly informed choice about performance vs cost vs features.
Therefore it doesn't in the long term benefit AMD or Intel, whic was probably the intention of this thread and the 3,000 before it. Consumers will now be able to look and buy something cheap, or pay more and get performance, whoever is offering it.
Taking a simplistic view without considering other components, if Intel offers an E6600 to Dell at US $200 and AMD offers the same price for say a 4800 X2, the consumer gets to pick. Now, for the first time, a Dell customer might actually start to choose based on the benefits of the different system components. With Core 2 Duo, in the near future, this decision may well greatly assist Intel. It might not later on. Either way, a good deal for the consumer and certainly not something for a fanboy to get all excited about.