and Ann Summers both unveiled new-look web sites at the end of last week.

While Play’s makeover was mostly cosmetic, Ann Summers finally unveiled the site built on the web platform that has been in development since the end of 2006.

As often happens now when retailers refresh or relaunch web sites, these two companies were both keen to point out that this was only one step on a ladder of continuing development.

Play says that customers can expect further significant changes on the site before the end of the year and Ann Summers has promised additional features now that it’s got the site’s underlying platform stabilised.

And for these two fun brands, that’s almost certainly the right thing to do.

On the web, retailers aren’t just competing with each other for consumers’ attention, but also the endless social and entertainment opportunities that exist, such as YouTube, MySpace, Facebook and so on.

Retailers aren’t competing with these social media companies for sales (yet), but consumers will still compare their sites when it comes to user experience. If Facebook can help someone reconnect with their long-lost primary school best friend in a couple of clicks, then there is an expectation that retailers’ sites should be just as simple to use if they expect consumers to buy anything.

While e-commerce sites are still relatively in their infancy, retailers have the chance to get consumers used to the idea that their sites will evolve continually.

Standing still brings two risks. The first is that it is much more expensive and time-consuming when you next decide to bring your site up to date. The other is that if consumers begin to expect everything to always be exactly the same, then they don’t take well to change. After all, just think about how annoying it is when you go to your regular supermarket where everything has been in the same place for years and find that it has moved the bread.