Adding twitter to wordpress.com blog:
There are two ways of adding twitter updates on a wordpress.com blog.
A] Adding twitter widgets:
1) Login to your dashboard.
2) Go to Appearance –> Widgets.
3) Add the widget Twitter.
4) Now, open the widget and enter the username and give it a title.
B] The second way is to use the RSS:
1) Go to your twitter username:
2) Scroll down to the bottom and look on the left for RSS.
3) Right click the RSS link and choose the option to copy the link (the naming of this option is different for each browser).
4) In your blog’s Dashboard, go to Appearance->Widgets.
5) Add an RSS widget from the Available Widgets on the left.
6) Click Edit for the RSS widget you added.
7) Paste the link in to box for Enter the RSS feed URL here and onfigure any of the other options. Click the Done button on the RSS widget options.
8) Click the Save Changes button at the button of the Current Widgets list.