Let's have a look at the Celeron family, because there we see processor versions ending in 1 as well - these are 64-bit enabled. And it gets even better, because a Celeron D ending in 6 likewise comes with EM64T. You might wonder why Intel didn't apply the 'J' for marking the 64 bit versions. Well, here is the answer: The 'J' suffix is used for showing XD bit support with Celerons, but only those not ending in 1 and 6. Make sense?

We should also mention that the Pentium D family called the 800 series is going to be enhanced by the 900 family soon. So far, there are not enough model variations available to confuse people, but with Active Management Technology (AMT) coming up - maybe not for the 900-series though - there will be more opportunities to branch out into new sequence numbers. In any case, we do not understand why the upcoming Pentium Extreme Edition had to be named 955, as this is the model number of the current high end desktop chipset 955X, which in fact - you probably already guessed it - will not support the new Extreme Edition flagship!

But wait, there's more! I haven't even mentioned the Xeon processor family or the mobile CPUs - the Celeron M and Pentium M. In addition to these, there is Intel's mobile Centrino brand, which marks portable devices that carry an Intel processor, chipset and wireless add-ons. And there is the new Viiv brand, that is going to certify digital home capable devices based on Intel silicon. Even without going into the specifics of these two platform brands, rest assured more model numbering confusion is on the way even as we speak.

'Choose the brand and number that's right for you.' Most end users simply do not have the knowledge to seriously choose anything here. At the end of the day, system purchases are going to be dominated by the type of device ("what can I do with it") and the price. However, for the technically interested customer, this is a nightmare.