This progression slash played on the Ellen show (starts at 3:47) : https://www.youtube.com/watch?v=TJFx6VOdCoEI hear it all the time, does anyone know what the progression is?

Moved to Learning Guitat & Bass :) 

it's based on a regular 12 bar blues played in a shuffle rhythm, however he doesn't really follow the standard pattern..

 

the standard progression is I - IV - V and usually is played in a pattern of: I - IV - I - I - IV - IV - I - I - V - IV - I - V and over again (which Slash doesn't really follow here)

so let's say you want to play a blues in E you'd play E - A - E - E - A - A - E - E - B - A - E - B..

 

the notes to play within this shuffle for instance for E would be the open E string, and on the A string you could "move" between B and C# (both belong to the E major scale.. they're the 5th and 6th)..

i think it's easier tabbed out:

e:-------------|-------------|-------------|-------------|-------------|B:-------------|-------------|-------------|-------------|-------------|G:-------------|-------------|-------------|-------------|-------------|D:-------------|-22-44-22-44-|-------------|-------------|-22-44-22-44-|A:-22-44-22-44-|-00-00-00-00-|-22-44-22-44-|-22-44-22-44-|-00-00-00-00-|E:-00-00-00-00-|-------------|-00-00-00-00-|-00-00-00-00-|-------------|e:-------------|-------------|-------------|-------------|-------------|B:-------------|-------------|-------------|-------------|-------------|G:-------------|-------------|-------------|-------------|-------------|D:-22-44-22-44-|-------------|-------------|-44-66-44-66-|-22-44-22-44-|A:-00-00-00-00-|-22-44-22-44-|-22-44-22-44-|-22-22-22-22-|-00-00-00-00-|E:-------------|-00-00-00-00-|-00-00-00-00-|-------------|-------------|e:-------------|-------------|-----------------------------------------|B:-------------|-------------|-----------------------------------------|G:-------------|-------------|-----------------------------------------|D:-------------|-44-66-44-66-|-----------------------------------------|A:-22-44-22-44-|-22-22-22-22-|-----------------------------------------|E:-00-00-00-00-|-------------|-----------------------------------------|

obviously this can be transposed to any key you like..