Online Check-in - Don't bother using the email boarding pass option at the moment!
There seems to be an issue with BA's online check-in systems at the moment. If you select the option to have your BP emailed to you, it takes a very long time to arrive. For instance, last Thursday I checked in at 9am for a 9pm flight and asked for my BP to be emailed to me. The emails arrived at 2.30am the following morning (i.e. over 5 hours after the flight had departed!). The same thing happened yesterday.
Of course, not a major issue, you can still go back in a print it off directly, or save the PDF version. But if anyone from BA IT is reading this, you might want to check what's going wrong with your email servers!