This month's Top Gear magazine lists the rather short tally of UK cars that arrive with iPod connection facilities as standard (rather than an extra-cost option):
Citroën C1; Peugeot 107; Toyota Aygo; Land Rover Discovery 3, Range Rover and Range Rover Sport; Hyundai Sonata; and Ford Mondeo, C-Max and Focus.
Top Gear does seem to have neglected the Smart ForTwo i-move special edition. Perhaps because it's a special edition, and therefore not really a standard car. And also because, rather than being iPod-ready, it arrives with an actual 20GB iPod as part of the package.