I'm a little unsure about what exactly fret board radius is. What exactly is it?

It refers to the arc of the fretboard.

The roundness of a fretboard.
A flatter one is supposedly better for bending and faster playing.
A more rounder is for the opposite, but I don't notice enough difference to care what the radius is... It wouldn't effect me buying anyway.

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• Fender American Series Stratocaster (Olympic white, maple)
• Gibson Flying V (dusty faded cherry)
• Fender 1969 Custom Shop Stratocaster (3-tone sunburst, maple)
• Fender Highway One Stratocaster (Honey blonde, rosewood)

Yep, tha larger the radius the flater the fret board.

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I have a strat that has a 12 fret board and a tele with a 7.25 radius. Which is flatter then? (Never really paid attention to that before so I didn't notice a difference.

Oh so 12 would be the flatter one. Thanks for clearing that up for me fellas!

My Tele has a 12" radius and I like it but which do you like better?

think of the fretboard as being the outside of a circle - the 12 inch radius would be a bigger circle - flatter, the 7.25 would be a smaller circle - more curved. I think its easier to bend on the flatter boards.

I just had my strat set up the other day, I usually use .11 strings. It has a 12" fret board and I can't bend the high e string past the ninth fret! Before I had it set up I could at least bend a step at the 12 fret. The guitar tech told me that the heavy strings make it difficult to have proper intonation and enough room to bend. Is this right? I don't really care about having low action, I just want to be able to bend on the upper part of the neck. Does having .11 or .12 strings on make that big a difference? I want to at least be able to bend up a step and a half.

I wouldn't think the larger strings would make a difference. Proper intonation should be able to be achieved regardless of higher action. With a 12" fingerboard, you shouldn't be experinceing issues with it fretting out. One of my guitars has a 9.5" fingerboard and .11 strings, and while it has higher action to prevent it from fretting out on bends, it doesn't, and is properly intonated.