Unlike all of the other companies you mentioned, we do *not* require you to give us your bank or credit card usernames, passwords, or account numbers in order to use our service. We allow you to upload a file downloaded from your bank -- in which case no software but the bank has your password -- or use one of our downloadable agents, the Wesabe Uploaders, which store your passwords on your own computer.
The export/import model may be appropriate for Wesabe's model of exploring the broad patterns in your finances, but I (as a consumer) want real-time aggregated numbers.
Update: it seems that Wesabe does support dynamic update - through a desktop tool. I should do some research ....
In a separate comment, Yodlee's Jordan appears t0 blame the banks
The challenging is having the large financial institutions of the world understand that there is a compelling driver for them to support these news technologies.
but cites a willingness to change
Yodlee is an innovative technology company and we are always pushing towards the best and most secure way to do things and we are able to implement quickly.