Here are a few things to to be kept in mind:

• Since this is the pre-holiday season, make sure you don't miss on the traffic. MS anticipates 50-60% transfer of Yahoo! Search Traffic to adCenter by this weekend.
• It is suggested that by 25th october , the accounts are funded with full budget to support the traffic from  Yahoo! Search and Bing.
• If there is a confusions regarding the budget, it is advised to allocate 1/3rd to adCenter.
• Keep a close watch on the bids, since the transition may cause some initial fluctuations.

For any help, there are various options:

• There are a plenty of useful tips and advice on blogs and discussion forums.
• Take help from Microsoft adExcellence tutorials.
• Tweet question to @adCenter on Twitter.

Last but no the least. Provide your feedback and ideas to the adCenter Feedback Thread.