My 10 plate GTD has both front seat outer bolsters 'drip' marked with water stains, I'm unsure if the seals actually leak now (we've had so little rain!) or the previous owner had it sorted, but I'm holding off cleaning the bolsters until next service (June....ish) and will bring it to the attention of the dealer.
If you look at the design of the door seals, I'm surprised we don't hear of more cars that leak!
I try to keep the top sealing edges of the doors scrupulously clean and make sure there's nothing interfering with the rubber or 'felt' of the seals.
I think the way a lot of cars are designed now, (with no roof 'sill' of years ago, or with the tops of doors encroaching into the roof area) if either of the front doors are opened in the rain (or just after a downfall) water will run off the roof straight into the interior!