I highlighted one notable absence there, but can't believe I missed another - and unfortunately, today it's been confirmed they've left.
Debbie is leaving Shameless. Such a shame - she'd kind of become the lynchpin of the show and the last series put her into a position where Fiona was the first series. It survived the loss of Fiona and Steve, Kev and Veronica and a few others, but I think Debbie leaving might have the biggest impact of them all. If it is to continue beyond the next series, I think the only option is to bring in a new family as the leading characters and axe the Gallaghers completely, allowing the show to regenerate Skins style. Otherwise bring it to an end before it's too late - seven series is a fantastic run nowadays for a UK drama, especially on C4.