20226 was released on 2/16/07. For now the only way to get it is to call *2 and speak with a representative. Tell them you wish to have your account flagged for a PRL update. Give them your mobile phone number if they ask for it. Then when they've done it, tell them thank you (
) and hang up. Call *2 again and you should get a prerecorded message saying that a free update to your service is needed. Stay on the line until you are told that the process is complete (it is just a timed pre-recorded announcement, but still...). Then hang up and check your PRL version under settings->device information. If it says 20225 still, then try a soft reset and look again. If it still says 20225 then you will need to call *2 back and try again (you don't have to ask for it to be flagged again--it will stay flagged until the PRL successfully downloads). Sometimes it can take a few calls before it works. Make sure you're in a good signal area when calling.
None of this is of any earth-shattering importance though. PRLs mainly deal with roaming settings so it's not a big deal for most people.