Someone might have a detailed technical answer for you, but I'd like to suggest that you find your own voice with the guitar rather than just try to emulate what Slash is doing there. Honestly, while I think Slash is a great guitar player, I thought the soloing in the video was really more just noodling.. it didn't seem connected with the rest of the band, more just "hey look at me" rather than a firm musical statement.

I watched a video a while back of Neal Schon (Journey) in concert(I think it was Live in Manila), and he did kind of the same thing during a guitar break/solo.. lots of flashy riffs and then out of no where he did this really melodic part that was just beautiful. He uses a whammy bar and sustainer, and he really used it tastefully, along with this nice little understated keyboard line. It sounded fantastic. Maybe it was just showmanship, but it really seem like Schon bled the part.. put his heart into it. I find that kind of guitar playing way more inspirational than some of these videos coming out now where it shows a counter for how many notes were played in x amount of seconds.

If you focus on how to play like Slash, you'll aways be compared to the original. If you allow your voice to come out through your guitar playing, you'll be an original. At least thats my 2 cents worth!