How many time have you been browsing in Firefox and something hang or crash, not many probably but when it does it takes down the whole browser. Now it seems Mozilla is taking a hint from Google’s Chrome, by splitting tabs into multiple processes that are independent of each other. So if one tabs crashes oh well close it and continue. The development of this project is in the beginning stages and could be up to a year to see a workable release but, it should be worth the wait.
Source: Mozilla Links