The guys of xperiancers blog have posted an X2 application update on the regular Sony Ericsson Update site at sonyericsson  this is not the full MR1 software release They mentioned in a previous post but a cab file that will add stability and improved performance throughout the device.  The cab provides updates to many applications inside X2, several are behind the scenes but make sure to check out the new and improved four-tab dialer. Thanks guys by the information.

Then see this video for a quick demo of how to install the update and to see some of the changes it makes.

Xperia™ X2 software update

Update Now your X2 here: http://www.sonyericsson.com/update