Post Pages give each of your posts their own unique web page, in addition to appearing on your blog's front page. The advantage to that is your readers are able to link to this particular post.
Here is another good question from a reader, Shrish. He wondered if it is possible to take this hack,Tweaking Permalink in Blogger, and use it for Blogger Beta. To re-hash from that post, in blogger posts, if you hoover over the timestamp a small popup will come up that says 'permanent link'. Unless someone is familiar with all the fine details of blogger, they won't find this link. This is a disadvantage. But, you can easily add the text 'permalink' to that time stamp to Blogger Beta too. First you must open Dashboard/ archiving/ check: Enable post pages. Return to Dashboard/ Template/ Edit HTML/ check: Expand Widget Templates. Locate this code and insert Permalink (with a space in front):
<b:if cond='data:post.allowComments'>You can see how to do this on Classic Blogger here: Tweaking Permalink in Blogger
<a class='comment-link' expr:href='data:post.addCommentUrl' expr:onclick='data:post.addCommentOnclick'><b:if cond='data:post.numComments == 1'>1 comment<b:else/><data:post.numComments/> <data:top.commentLabelPlural/></b:if></a>
</span> <span class='post-timestamp'>
<a class='timestamp-link' expr:href='data:post.url' title='permanent link'><data:post.timestamp/> Permalink</a>
</span> <span class='post-icons'>