why not twitter in top 5?

[tarunsarien5]

Google, facebook has PR-9 and twitter has PR-10 ,

But why twitter is not in top 5, as they don't have any drawback, millions user ,Having daily high traffic, used world wide , very popular .

Please share your views, why twitter is not in top 5.

[chandan001]

Hi,
Mainly twitter is micro blogging site and facebook are social networking site where we chat, share and create more pages.

[Roger14]

hi

twitter is just a micro blogging site and facebook is social networking site, which make major difference between them.

[tehminamlk]

Twitter don't offers to create a fan page to promote your business, and there are not any colourful images, or videos in twitter to keep sticky with it, it is just a connecting network, best for keep in touch with whole world and get frequent updates from countless sources in very less time. You can say it plays its role as a reporting agent, not as an entertaining platform, these are my personal views, may be nobody agree with me. But i really feel facebook is much more colourful and have attractions like apps, and games etc that's why it is not in top 5.