The leaks have just been pouring in recently! LOu let us know that OS 188.8.131.521 for the Bold has just made its way onto MegaUpload at this link:
Keep in mind this is a Beta OS!!! Let us know what you find in the comments!
Note: Do this upgrade at your own risk because it may render your device unusable if you are not familiar with OS upgrades, this is a Beta OS and not an official release.