Not necessarily -- I actually think it is subversively conservative. The irony of that show was that by the end of the series, all the girls had basically grown sick of their "glamorous" lifestyles, gotten married to a more-or-less normal guy, settled down, and started having children. At the beginning to the series, these girls were ultra-liberal Manhattan sluts, and by the end of the show they had all discovered that a much more conservative family-oriented lifestyle was their path to true happiness. No, they don't become bible-thumpers, but they all strongly gravitate toward more conservative family values as they realize it is their promiscuous ultra-liberal lifestyle that is making them unhappy.
I watched the show off and on over the years. I know the show is lambasted here regularly, but it was actually a slow motion deconstruction of the supposedly glamorous lifestyle of these women and how unhappy it actually made them. The story line was basically all four of those girls discovering how profoundly unhappy they were with their freewheeling, care-free city lifestyle, and finding real satisfaction in mundane tasks and building families.
I don't know if it is intentional, and you have to watch quite a bit of it to see the clear trend. For regular watchers of that show, I've seen positive influences on the way they think about such things, as it showed the real negative consequences of these women choosing to live the way they did.
In some ways, it is like South Park in that you won't see the subversive nature of it if you only see a small snippet of it and it will come across as profoundly liberal. But in the big picture, some clearly conservative ideas are being promoted as a common thread throughout the episodes.