They are definitely somewhere. Xanga knows people are pretty attached to their blogs, so I'm sure they've done everything to preserve them. You should be able to download your posts from your Dashboard. The first day I logged into the new site, there was not a link to my blog archive, but today (a couple days later) there was a link. It was in a yellow bar at the top of the dashboard. Be patient and check back over the weekend. If it doesn't appear, I would update this question with the fact that it still hasn't appeared. ...All the best. -Colby

I'm not affiliated with Xanga, but in order to keep blogging, it looks like you have to:
1) Download your blog archive (a .zip of .xml files) from the Dashboard. There should be a yellow bar with a blog archive link at the top of the page.
2) Pay for a subscription to Xanga 2.0, have financially supported Xanga 2.0 relaunch, or have paid for Xanga Premium.
3) Find the Tools link on the Dashboard page and import your blog archive

If you, like me, have never given Xanga a dime, and aren't going to now, at least you have access to your blog posts saved in the blog archive.

Here's more info:
Your blog will not be available to be hosted on Xanga unless you pay a subscription fee. If you wish to remain with Xanga, and have not purchased a subscription you can do so here: https://xanga.crowdhoster.com/relaunch-xanga

If you do not wish to pay the yearly subscription and wish to move to another blog hosting service -- the process is fairly simple. Your blog archive is in a WXR format. Wordpress.com makes the transition simple in that regard. If you have made an account on Wordpress.com follow these instructions. http://en.support.wordpress.com/import/
Other hosting services may have different requirements, and you may need to look for conversion tools or copy/paste the entries manually.