I might be a little late on the uptake, but I found a couple of apps available on Cydia catering for copy n paste. "Clippy" and "hClipboard" allow multiple text selection (for copy or delete) and text copied can be pasted between apps (for example, copy text from email and paste into an SMS) Also allows copying an SMS (double tap SMS to copy) which is a workaround for lack of SMS forwarding.

Only downside at the moment is that you need to be a text editing situation to copy text. IE, to copy text from an email you need to click the REPLY button first, then copy the text and paste it into a new email etc. And as of yet, it doesn't support copying text from a webpage (bummer)

But quite usefull

And yes, before one of the Anti-Apple/iPhone members pipes up, we ALL know it's such a basic thing that should have been included, but it wasn't, and at least this is a workaround for people still waiting for it to be included!!!!