Not sure how much response you have gotten, but I have just started a Colorado focussed blog and we discuss Mountain Biking.  Here is a link to an article on our blog about improving your Mountain Biking skills.

http://nextascent.wordpress.com/2009/07/11/10-ways-to-improve-your-mountain-biking/

We'd love to hear more about what other things you'd like to see.

Hope that helps.

Best advice of all...just get out and ride

Eric

The simplest advice it to ride a lot with riders better than you

I would recommend Brian Lopes's book on Mastering Mountain Biking Available through the IMBA website (Join IMBA and support the trails)

Most of all have fun

Go to Rideyourbike.us and Checkout some of our tips

10 tips for your first Mountain Bike Race

23 Feb 2009 by Michael 

Mount Snow Mountain Bike Racer So you want to enter a mountain bike race but you are not sure if you are ready or what to expect. Here is some information to help you . Let me start by saying that everyone who is serious about riding ...

RideYourBike - http://rideyourbike.us/ride.htm

Ride your bike through the winter with these dressing tips

6 Dec 2008 by Michael 

In this article I will try to provide some guidelines and tips to keep you warm and dry without overheating. Dress in layers: I am sure you have heard this one because it is sage advice. This is the most important part of being to ...

RideYourBike - http://rideyourbike.us/ride.htm

tips for getting physically fit university of cali...

28 Mar 2007 by Michael 

tips for getting physically fit university of california, berkeley wellness letter march 09, 2007 physical fitness -- the ability to carry out daily tasks with vigor, without undue fatigue and with ample energy to enjoy leisure-time ...

rideyourbike.US - http://rideyourbike.us/ride.htm

How to find the Divine Line.

10 Jan 2009 by Michael 

What follows are some tips to help you pick better lines, clear difficult sections, and keep on rolling (rubber side down). 1) Look where you want to go – I can’t overstate the importance of this one enough. Your bike will go where you ...

RideYourBike - http://rideyourbike.us/ride.htm

find a state of flow* from mastering mountain bike skills by brian ...

17 Nov 2007 by Michael 

here are some tips to help you achieve flow more consistently and in crazier situations. break ’em down. break big tasks into small components. if you’re an intermediate jumper and you try to nail a technical 10-pack all at once, ...

rideyourbike.US - http://rideyourbike.us/ride.htm