Twitter’s popularity has exploded lately, but there is one big flaw with their product. Its incredibly easy to reproduce by established companies and integrated into their products.

According to Facebook’s blog, they have added features that are strikingly similar to what Twitter offers. It takes all of your friends and rolls them up into one page that provides updates on what everyone is doing, provides a picture, etc. You can also get updates via RSS or SMS, or update your Facebook page directly from your cell phone.

With Facebook’s resources, as well as other companies looking to add similar services to their products, it looks like it is going to be hard for Twitter to compete a year or two from now. If you use Twitter, wouldn’t you rather use a similar service built into your Facebook or MySpace page?

If I was Twitter, I would look into ways to make money while its still there, then try to sell out to a large company while it still has value.