On a fundamental level, the 341 Meeting of Creditors is the same regardless of chapter. The meeting presents an opportunity for creditors to be present while the debtor or debtors is being examined under oath by the trustee administering the case. Most of the time, creditors do not show.
In Chapter 7 341 Meetings, the meeting is driven by the trustee's examination of the debtor to determine whether there are assets that can be liquidated for the benefit of the unsecured creditors in the case. These questions focus on any unexempt personal or real property of the debtor, or if there have been insider or preferential payments made to any unsecured creditors, or if there is the right to any money or lawsuits that could bring money to the debtor. Most of the time, a no asset ruling (or a report of no distribution) is found and the meeting does not require any more indepth questioning.
In Chapter 13, the focus is on much of the same questions, but at the same time ensuring that the proposed Chapter 13 plan will work to pay back unsecured creditors. Because a Chapter 13 is not a liquidation of your assets but rather a debt repayment bankruptcy, the focus of the meeting is to see if there are any unexempt assets but only to the extent that it could drive up what is to be paid to unsecured creditors. The true thrust of the meeting, then, is on ensuring that the schedules are accurate and that the Chapter 13 plan is functional.
Obviously, this means that the 341 meeting for Chapter 13's is longer. The questioning is more thorough usually and requires more time from the debtor. Like a Chapter 7, most of the work is done ahead of time by the attorney and the client to ensure that the information is correct. But here, if there are any amendments to be made to the Chapter 13 plan or elsewhere in the case it will be recommended at the 341 meeting. Because of the complexity of the Chapter 13, you can see why it would be important to consult a Chicago bankruptcy attorney prior to the meeting.