I'm a Treo 600 user who recently converted over to WM5. The program I miss the most from the Palm is SplashMoney (http://www.splashdata.com/splashmoney/index.htm).

It worked perfectly for me. I downloaded a lot of free trials on Handango and couldn't find anything that worked similarly enough.

Here's my list of essentials:

Needs to support checking/savings accounts and credit card accounts.
Needs to be easy to add, edit, and purge records
Needs to be able to do recurring charges/deposits
Needs to show running balances on each accounts, and running balance on ALL accounts combined.

I don't need any forecasting or anything that shows pie-charts regarding how I spend my money. I just want running tallies so I can keep on top of all of my purchases and deposits.