It wasn't obvious to me, but selecting text (from a document / messaging) is done just like on windows.
Hold shift and select with the scroll wheel or touch. You can then cut/copy/paste/delete with that selection. This doesn't seem to work with web pages (except for forms)
For cut/copy/paste as mentioned you can use the Menu c,x,v. Or you can use touch. In messaging for example, if you long-touch on the text you get a menu for: Select All, Cut, Copy and Paste. It seems that sometimes you must double-tap-long-touch. Meaning, tap once and then tap-and hold until the menu shows.