Oh, I don't know...
I can't off the top of my head think of any really intellgent pop artists, but there are a few individual songs that have a certain something.
Common People- Pulp- Britpop. it's You cannot say that that is not intelligent.
Stupid Girls- Pink- Punk Pop. Pink fuses punk and pop very well- her songs are pop but this song was standing up against the norm, laughing at convention... just like the best punk.
She's my Man/Mary- The Scissor Sisters- Disco Pop. SMM is very well written and it has good lyrics. It is also about something other than just partying. Mary was, if I remember, dedicated to soembody who had died, so it has personal meaning to the band. This is what I like about the Scissor Sisters- they are a camp pop band who operate like a rock band- working themselves up rather than being manufactured, getting their own image rather than just following the trend, and thinking about their music rather than having it written for them or going for soem easy 'get on the dancefloor' theme.
All the things she said- TATU- Pop. It's quite deep really, and it annoyed me when the singers called it a 'bit of fun for their husbands' because it's actually a very emotionally charged song.
I think the reason pop music lacks intelligence is becasue most successful pop bands are manufactured- so they get given safe songs about love or partying and are styled in the latest fashions. To big record labels there is no room for anything risky or controversial that might lose buyers or upset the censors, so the same old stuff gets churned out.
As I said, this is why I have a lot of time for the Scissor Sisters- because they've done it themselves rather than get moulded by a record label. How many other high-profile pop bands do you know who have their own guitarists and drummer?