I have this problem as well. The option to ask the Jarl for work never appears for me. Before the updates (I hadn't played Skyrim in 2 months) I was able to get the questline started rather easily. I have now completed the Thieves Guild and tried pretty much all the quests, nada.
Maybe try clearing your cache (erasing the updates) and trying? Might work. Might cause an error where it says "This is a save with an update and can't be played without it" or something like that.
If you don't know how to clear your cache I made a tutorial on it: http://www.youtube.com/watch?v=i5zXCVy_jOA&feature=BFa&list=PL624F29BFB83024DF