1.02.20 is the most recent version officially released on an OTA (over the air) update. 1.02.27 is available as a beta for download and install via USB (see HERE - click), but be aware of the wrinkles (see HERE - click).
1.02.20 is the current 'release' version. However, there is a beta version available, 1.02.27. It has not been broadcast via an OTA (over air update), so a scan will not pick it up.
Some people have reported having some issues since they installed 1.02.27, although nothing 'concrete' so to speak. I have been using it and the custom firmware associated with that build since release and, to date, have not had any problems whatsoever.
Have a look ate the Wiki, a link to which is in the top left hand side of this page.
Ok guys done the up-grade without any problems. V.Good How 2 instruction file with the down load.
To be honest Iv'e had so many Green screens, twitches, freezes and shut downs of late I had to give it a go.
I am not a Techy but I will let you know how it goes.
Many thanks to you all.