My new Samsung Galaxy S2 (Orange) comes with "Samsung Social Hub" support. When I add an email account, this is very easily configured and supports push & all bells and whistles with this service.

I find precious little technical detail. For example, is my email now going through Samsung's servers? What is their privacy statement? How can I be sure their service uses the highest security options supported by my server; e.g. SSL instead of plaintext?

Too many unknowns. Samsung provides an FAQ, which doesn't answer any of this.

Any insight would be greatly appreciated.

I, and many others, don't use the Hubs....To be honest you are better off using the individual apps. For Email I use K9Mail (free from the market). Using individual Facebook and Twitter apps is also faster than the Hub.....The stock SMS is OK but GoSMS is better IMO>
I believe the hub just acts like any other email client and just downloads straight from the email site...

Agreed. I haven't bothered to touch any of the Samsung 'hubs'. Completely unnecessary software IMO.