This post applies to SharePoint enterprise version and Office 365.
A couple of weeks ago, I wrote an article for the The Microsoft MVP Award Program Blog. Some of you may have heard my rants about how keeping the approval process inside InfoPath is a better method than assigning task through workflows, because then your data is all over the place. In this article, I show step by step how you can still assign task from a workflow and keep the user interface simple by inserting the form’s fields into the task form itself. There are various permutations of creating an approval process in SharePoint, and this is just one of them.
MVPs for Office 365: SharePoint Designer Workflow Tasks and InfoPath 2010
Here is a screenshot of the end result. You can see that you’re still on the task form, but all of the pertinent fields from the original for are also right there, so that end users don’t have two different places to go.