Originally Posted by: Jolly McJollysonC major has the same notes as A minor, yes, but they're not the same scale.[/quote]
Excellent point.
[QUOTE=Jolly McJollyson]Let's say someone's playing a C major progression. If you play the licks you normally solo with in A minor, they're going to sound very strange and out of place because they emphasize notes which one would not normally emphasize in C major.

Dude, this sentence nails it.

I've heard this at least a million times. It's painfully obvious that such a solo sounds like someone that knows a fretboard pattern yet has NO CLUE what a scale or a chord is.

You actually can use the exact same licks and patterns in different contexts but you really need to be aware of the scale degrees.

C Pentatonic major:
1st - C
2nd - D
3rd - E
(no 4th)
5th - G
6th - A
(no 7th)

A Pentatonic minor:
1st - A
(no 2nd)
3rd - C
4th - D
5th - E
(no 6th)
7th - G

Adding the E-flat is a minor 3rd in C major and a flat 5th in A minor. Some people call this the "blues scale", some call it a "hexatonic blues scale" (because it has 6 notes of course).

Consider this classic "blues-pentatonic lick":

|------------5--------------------------|
|---------5-----5--8-b-(10)-------------|
|-5-b-(7)-------------------------------|
|---------------------------------------|
|---------------------------------------|
|---------------------------------------|

Bending that G up to A at the end sounds great if you are playing chord with an A in it, or a part of the melody that exphasizes an A. But if you are playing in C major and doing this over a C major chord, it's like "Huh?" LOL.

On the other hand if you are in C major but an F major (the IV chord) comes around, this can be a great, tasty sounding choice - because the F major chord has an A in it!