The '4004 had a "logical" havard architecture. Logical because it implemented with single 4 bit multiplexed bus structure (sound familiar?).

Erik is correct when he indicates the '4004 is the well-spring from which all intel proc's flow. But as i watched the processor lines mature, it sure seemed like the '4004 was the precursor of a line that directly evolved directly into the '8051's of today.

The '8008 always looked like the true precursor of the 8080/85/86/186/Pentiums of today.

The above is just impression but those acquired as these parts introduced, matured, and died. I still have a '4004 in a box somewhere.

regards,
p