If you’ve got a hankering to try some software from the next version of Android, it’s been pulled from Nexus 4 and is available for Sense, AOSP, Touchwiz and most other Ice Cream Sandwich flavors of Android and above.
In other words, you must be running Android 4.0 or greater, and you should probably have a nandroid backup if you’re rooted. Installable apk versions, as well as flashable .zips, are available for download now.
The new keyboard from Google includes gesture typing (ala Swype) and integrated voice typing. While the current release of the keyboard is probably not how it’s going to look in the final release of Android 4.2, it’s a working Swype competitor with a mean penchant for understanding what you say.
If you decide to give it a go, let me know what you think of it and what ROM you’re running.