Google is only beginning to roll out these vanity URLs. Currently, only a few thousand verified and well known people and brands have it, although they will be adding more over time. See this post for (not much) more information.
In the meantime, you should be able to create a redirect from your own website to your profile. (It may be argued that this is a better solution, even.) You can also setup a Google+ Badge to let visitors to your website go to your profile or follow you directly from your site.
A workaround for anonymous smart phone users to view Google+ "Posts" pages without logging in is to first navigate to the user's "Photos" page, such as this one, and then click the user's name (i.e. "Philip Durbin") to get their "Posts" page.
No. No such feature is available yet. And if you follow the other social networks out there, they also follow the same trend. The about page is usually never the landing page. It's a way of promoting the content of the web service and encouraging communication.
Usually professional sites like LinkedIn follow that trend, as in professional field the about page is more important than the content by that user. It is more of a resume and less of a social profile. But for a simple social network, the activity feed gets more priority.
Best Answer
Google is only beginning to roll out these vanity URLs. Currently, only a few thousand verified and well known people and brands have it, although they will be adding more over time. See this post for (not much) more information.
In the meantime, you should be able to create a redirect from your own website to your profile. (It may be argued that this is a better solution, even.) You can also setup a Google+ Badge to let visitors to your website go to your profile or follow you directly from your site.