It seems ASUS often releases firmware update to its products. Today ASUS Eee Pad Transformer Prime TF201 gets 10.4.2.18 update. All customers can get this update over th air. If you have not got it yet, you can also download and install it by the following link manually.
The 10.4.2.18 update for ASUS Transformer Prime TF201 fixes many issues. For example, it fixes the issue that in ASUS Spanish(US) and ASUS Dutch(Holland) IME, some characters cannot be typed or cannot be typed correctly, the web page compatibility is improved, besides, it upgrades Polaris Office to 3.5-build 5r16148FV06, and so on.
Check for 10.4.2.18 update on your ASUS Transformer Prime TF201 right now, you wil find many new features on your tablet.