I just recently setup another email account on my iPad, when viewing the unified inbox, is there any way to make it display to which account the message was sent?

The way I do this is to 'touch' the 'To:' field of a received message and it pops up box with the email address that the message was sent to.

So, if you had, say, two email accounts 'tim@tim.com' and 'tim@person.com' then, if you touched the 'To:' field of a received message, one of these email addresses would be displayed.

This is probably not what you want - I suspect you're looking for a way to get the iPad mail app to flag each email with the account that it was received from and I don't think there is any way to do that.

Tim
Scotland