Representative Expression

But despite me trying to allay peoples fears, there are still a few things I would do beforehand if you want to protect your months or years of hard labor.

Steps before moving to the New Blogger.

This following step doesn't just refer to moving to the new blogger, I can't repeat it enough, but it is something you should do before making any changes to your blogspot template (and I mean any...).

Backing Up the Blogspot Template

• Log in to your blogspot account.
• Click on the template tab.
• Select ALL of the text within the template section (press Control A (windows))
• Copy the selected text (Control C (windows))
• Open a notepad or similar editor.
• Paste the contents of the clipboard in to notepad (Control V (windows)).
• Save the notepad document on your PC.
  I tend to save them using a date time format (26FEB2007_blogname.txt)

I shall repeat it once again, but you should be doing this prior to making any changes to the template no matter how trivial you think those changes maybe.
I've been a blogger user since year dot, I've had more blogs than hot dinners, I've been there, seen it, done it, but that still doesn't stop me from hitting the wrong button and losing months and months of changes once in every blue moon. 
An extra couple of steps will mean a lot less heartache if (or when) you do make an error.
Another advantage to having each backup file date time stamped is that you can always go back to a template if at some point in the future you decide you don't like the changes.  You may for example also have had a snippet of code a few months ago that you deleted, but now want to bring back.
(This is actually a form of configuration management and is a good practice to get in to).

Backing Up your Blogposts.

If you are really paranoid and have a few days on your hands (depending on the size of your blog), you can if you want decide to backup your blog posts.

Bloggers own guide can be found here: http://help.blogger.com/bin/answer.py?answer=41447

Now a word of warning.  When I think of a backup, I think of a process whereby I take a copy of something, and if something goes wrong, I can restore it using an old backup set.
One thing to bear in mind with the 'old' blogspot backup profile is that there is no direct method of restoring a backup file that you have created with the process above.

Assuming you have less than 999 posts, all you end up with is a single file containing all of your post data.

Another point to note is that it does not contain your images.  The resulting file will contain just the HTML code in your posts.
Now in theory, the images should stay where they are, so the HTML code shouldn't change.
You should always keep your images locally backed up if you are posting them to a free file/image hosting service.
(Which reminds me of another 'pet peeve' of mine, never hotlink to an image on someone else's web server/page {unless you have the owners prior permission}.  This is called bandwidth stealing and gets right up my nose.  You should always download a copy of that image, save it locally, and then upload it to your own web server or free file/image hosting service).

Is it worth Backing Up your posts?

It all depends on how fearful you are of losing your work, and how much spare time you have on your hands.
If you have a large blog with hundreds (or even 1000's) of posts, then it will take an age to create the file.
If you host your blog on your own web server then the process can take even longer.

You also have to make a number of changes to various settings on multiple tabs in order to create the backup file, and these have to be set back to their original settings once you have completed your backup.  I would also advise that you make a note of each and every change you make (preferably by copying and pasting the original settings in to a different notepad file).

It all depends on how much you fear losing your work.  As far as I know, the transfer process is reliable, but at the end of the day, it is your hard work, time and effort.  Therefore it is your call.

One good thing to note is that one of the better new features of the new blogspot is that it has a much simpler backup process that creates the backup file and allows you to save it locally without the hassles of making millions of changes.

Time to Move On

Ok, so you've made the backup's, you are ready to go.
So what is next?

Simply agree to the terms of service and hit the continue button.
You should then see the following screen:

On the next screen you will be presented with the choice of assigning your old blog(s) to an existing gmail account, or create a gmail account (if you don't have one, or want to keep things separate to your existing gmail account).

Once you confirm the settings above and continue, you should see the following screen:

Assuming everything went Ok, you should get a mail similar to the following:

Congratulations! Your move to the new Blogger is complete.
You can now access your dashboard at http://www.blogger.com/ using your Google Account and start using the new features right away.
Happy blogging,
The Blogger Team

And that is it. You are now using the new blogger system.

Summary

As you can see, the most painful part of the process isn't the moving over itself, but

• the preparation and work required if you decide you feel the need to backup your blog before you move.
• Or perhaps the biggest pain is the wait you have whilst you are waiting for 'that' confirmation email.

You next biggest headache will be familiarizing yourself with the new blogger features.
But fret not, you won't even notice the changes when you have moved.
Most of the new features are related to the new template styles. For the time being whilst you are familiarizing yourself with the new blogger, continue to use the old template style.

I have converted or helped convert well over 200 blogs from the old system to the new one, and as I said above, I have only heard of one instance where the conversion failed and it was referred to blogspot technical support.  None of the changes have resulted in a loss of data.
I have though had several users contact me after they had played around with the new features (mainly the templates), only to realize that they had lost all the template changes they had made to their old style template.
So I repeat again, backup your template (date time method), make a note of all settings, and RTFM.

Before playing with any of the settings on the new blogger system, go to http://help.blogger.com/ and familiarize yourself with the new features.

(I'll leave the full version of this article on the main page for a few weeks and then I'll change to excerpt mode).