If you don't mind, is there any place, forums, threads or otherwise where I can find out rough times for those who applied in January 2012 and when they are expected to have their application processed successfully ? What factors can delay a spouse naturalization ?
There are threads in the timeline section of the nationality subforum where many members have posted experiences. You can refer to those as an indication, but they are not conclusive for all applicants, you don't need to worry about a problem with the application if someone has been approved before you. If all documents were sent nothing would delay your application specifically but that doesn't necessarily mean it'll be processed at the same speed as other submitted at the same time.