4 beats - not notes
The most common note is a quarter note, this is true, however half notes take 2 beats, whole notes 4 beats, dotted notes take 1.2 times whatever time period they would normally occupy (IIRC - its been a long time since I was a competent dot follower) etc.
So going to back to the riff for Satisfaction in tablature:
E-|-----------------------------------------------------------|
B-|-----------------------------------------------------------|
G-|-----------------------------------------------------------|
D-|-----------------------------------------------------------|
A-|-2--2----2--4--5----5--5--4--2--2--------------------------|
E-|-----------------------------------------------------------|
it is quarter half quarter quarter half quarter quarter quarter quarter quarter
Timing of notes is just as important as pitch in determining recognizability/melody.
"Whenever you find you are on the side of the majority, it is time to pause and reflect" --Mark Twain
"The significant problems we face cannot be solved at the same level of thinking we were at when we created them." --Albert Einstein
"This is still a dangerous world. It's a world of madmen and uncertainty and potential mental losses." --George W. Bush