Intel to ‘revise’ Pentium M naming scheme : Intel is to introduce a new processor numbering scheme when its 65nm ‘Yonah’ chip debuts early next year, sources from within Taiwan’s motherboard maker community have claimed.
The four letters work as follows: E indicates a TDP of more than 50W, T for 25-49W, L for 15-24W and U for under 14W. With Intel’s strategy directed towards building chips with ever higher performance per watt ratings, the Yonah numbering scheme may well extend beyond the Pentium M to other mobile processors and quite possibly desktop and server chips in due course.
Liviu Nastasa 
Pentium 4, Pentium 4 M, Pentium M, Centrino, Celeron, Celeron M, Pentium D, Pentium Duo, Celeron D, and their chipsets: all this 845G, 845P, 845PG, 845B, 915X, 915PB, 975X… it’s really confusing. Way to go Intel!