A small update was released for the Samsung Galaxy S II for T-Mobile back on the 16th. It was a small update that largely went unnoticed by many of us. The update moves your Galaxy S II to Software Version  T989UVLH1. It is still Ice Cream Sandwich and only offers two improvements. One of which is a simple ‘Bug Fix’ listing. The second however, is a bit more interesting. This update also offers ISIS/NFC Update.
Looks like T-Mobile is getting ISIS up and running. Now the few people who we have seen comment, don’t seem to see an app for it. We assume then that this update probably is just laying the ground work for when it goes live.
For those that are a bit lost, ISIS is the carrier equivalent of Google Wallet. The really cool mobile payment system. T-Mobile, Verizon and AT&T are all on board with making it happen. Sprint already has Google Wallet but is also thinking about creating their own version. A little competition is always a good thing, but we often wonder how much carrier controlled payment systems could be fouled up. ISIS was said to be coming this summer, with summer coming to a close really fast, they better get a move on it.
The good news though, if this update starts prepping the device for ISIS, then we can assume that a simple update to any device on all carriers supporting it will bring the service. This is much better than having to wait for a new device to launch that you want that has it built-in.
Source: T-Mobile Support via AndroidPolice