I rooted my phone as soon as I bought it from a retailer. My Samsung galaxy W is just 1 week old and I rooted it 2 days ago and it is working great till now. I rooted it without any customized ROM, just waiting for CM 7/9. Yesterday I installed kies 2.0 in my windows pc and then connected my Samsung galaxy. As soon as I connected my phone I found that there were new firmware updates available over there.
But now the problem is that I rooted up my phone and I am doubtful whether it is possible for me to upgrade the firmware. I am doubtful just because I have already uninstalled most of the system applications especially the Samsung Bloatware. Please let me know whether I should carry on with firmware update from my current update 2.3.6.