A friend of mine who applied last fall (September, approx) has repeatedly been promised his PR card on such and such a date, only to have the date put back. The most recent date he was assured he could have an appointment to pick up the card was July 7. I'm not certain if he actually received it or not, yet.

However, he has been to the UK twice since Jan 1, and not had any problems returning without a PR card. He's kept the paperwork showing that he's applied. 'Course he was also flying BA, and they assured him they would take care of any re-entry problems for him. (He's also recently applied for Canadian citizenship.)