I've become a little confused here. I've heard many guitarists refer to this as the "blues scale" - 1 b3 4 b5 5 b7 (this is the minor pentatonic including the b5 "blues note").

But I've also heard guitarists refer to this as the "blues scale" - 1 b3 4 b5 b7. Yes, this is is just the minor pentatonic with blues notes, minus the 5th.

So would I be correct in saying that the "Blues Scale" is the minor pentatonic with the b5 "blues notes"?

Any and all help is appreciated!
Pentatonic Minor Scale - 1 b3 4 5 b7
Blues Scale - 1 b3 4 b5 5 b7

In essence the blues scale is just the pentatonic minor with the added blue note, which is a flat fifth
Quick blues lesson: you can use any note in any key, so long as you use it correctly.

There are very many blues players who will sneak in b3's, b5's, b6's, b7's, you name it into their playing. Usually these come in the form of chromatic passing tones.

You can't hang on a note that's not in the key you're playing in, unless it fits over the chord you're playing it over. Well, it's not to say you can't, just that it will sound really dissonant and "wrong". However, if the note is played in a flurry of faster notes, it can be used to great effect.

Examples of chromatic passing tones: Larry Carlton's guitar solo in the studio version of Steely Dan's "Kid Charlemagne" features a couple simple arpeggio licks with chromatic passing tones thrown in.
Yeh my old guitar teacher used to do that alot, he called it the super blues scale. It's basically a chromatic scale without the b2. It's a great example of how "it's not what you play, it's how you play it"