Has anyone use this sucessfully: http://developers.marketo.com/blog/make-a-marketo-form-submission-in-the-background/
I'm assuming that it's used when you're passing data from one data capture element to another on a non marketo page.
Hi Sarah Greig,
Yes, this is used primarily when you want to use a non Marketo form, typically on your CMS, and yet capture the data, have the lead associated with the cookie (provided there is munchkin code on your page) and log a "filled out form" event in the activity log.
So it can be handy if you just want to keep the form building tool in place. It also very useful when you need to associate portal registration or login to Marketo, while keeping the portal own form for subscription or login, since they cannot be replaced.
We use it many thousands of times a day (since before that blog post). Like Greg said, there are few different scenarios. It's great for relaying info from a "cool" demand gen plugin like SumoMe or OptIn Monster, which might even be running on a Marketo-hosted LP.
Have you used for any of the self service calendars e.g Calendly - Sarah Greig .