There seems to be a lot of overlap between XP and Scrum in the Agile world. Somewhere I remember hearing that Bob Martin suggested at Agile 2005 that everyone was moving towards an Agile process that looked pretty much like Scrum with the XP engineering practices. I saw a little background on this on the scrum-development mailing list from Mike Beedle:
Many of us were in a room full of people — a group that included Ron Jeffries, at Snowbird 2001 when Kent Beck said: I stole Scrum and used Scrum in XP (paraphrasing).
This appears to be about where we are with Agile adoption, though we have quite a ways to go on a lot of the XP engineering practices.