Now there will be a total of 9 classifications for this one type of CPU, all related to how much power the CPU requires. That's fairly important when it comes to mobile CPUs, and since this one can range from needing more than a beefy 40W of power (pretty hot for a mobile) all the way down to less than 12W, having more separation does make sense. Sadly, most naming conventions today mean very little to the consumer. Considering how much less of an impact clockspeed has on a CPU performance compared to so many other factors, really the only way to know what you are looking for is to do research.
The Montevina core will eventually be made available as a quad-core mobile processor, among others.