I am a huge fan of the blues and improvisation, and i enjoy learning theory and really enjoy learning scales. I can figure out the diatonic and pentatonic scales in all 12 keys in about 5 or less seconds. I also know the 5 positions for each. What is next? Can someone pleae describe the theory behind modes. I dont get modes at all. What other important scales should i learn?

Also is it important to learn what notes are in each scales?
I am certain there is a thread about the modes and such.

Good scales to improvise:

Minor Pentatonics,
Major Penatonics (people seem very weak on these for some reason?),
Modes from the Major Scale,
Modes from the Harmonics Minor Scale,
Modes from the Melodic Minor Scale,

Most of I would say learn your Arpeggios REALLY WELL. Arpeggios bring so much possibilities within improvising and can so easily break you away from scalar and box playing.
Modes really arent all that complex, once you understand them.

First of all, if you're using a major chord progression like Gmaj-Cmaj-Dmaj, you use (usually) use the appropriate major scale, G in this case, and all the other modes really have little bearing on the song's feel. You can use them of course, because they are all notes from the key of G, but just because you move up to the A Dorian fingering, you wont be in A Dorian, you'll still be in G maj because the G major chord is the tonal cener of the progression.

If you really want to begin to experience all that modes have to offer, you want to try making some modal progressions. Let's stick with A Dorian for this example. It still uses all the notes from G major (GABCDEF#), but we're going to make the A minor chord, the ii chord in G major, the tonal center which can be also be said another way that it will now take the position of the i chord. Lets use a similar progression to the previous example and make it Amin-Dmaj-Emin.

This progression is clearly not G Major, that chord isn't even in it. The fact that it starts with A minor and moves to D major (which contains an F#, so A minor is unlikely) are strong clues that this progression is A Dorian. Now you can use the A Dorian fingering to improvise and make something that sounds entirely different than Major or Minor progressions.

There are actually a lot more to modes than that, but this is a logical step forward. Let me know if you'd like me to clarify anything, or if you're still confused.