Firstly, Google has provided this handy guide for how you can download your feed data. Prior to this announcement, how many of us even bothered to back-up a list of who we were following anyway? So it's a good opportunity not to lose touch with those feeds you adore.
Secondly, if we migrate to a new reader, we can have a good look at some of the subscriptions we had and consider whether we still need them. Are you still following a pregnancy news feed even though your baby started school this year? We all have changing interests.
Thirdly, you won't lose the feeds of the blogs you are following. You just need to transfer to a new reader.
A quick check reveals some of the following as options:
Personally I installed Feedly for Chrome. Here's a few tips about transitioning from Google Reader.
I suggest making a decision while Google Reader is still active and not waiting until your data is gone and you can't remember who you followed. Already, I am loving the new look of Feedly and the fact that the previews are so clear, it's like a personalised newsletter. Below are a couple of screen shots from my Feedly.
Who knows, maybe you'll reconnect with feeds you forgot you even followed.
UPDATE - 16th March 2013
My friend asked for some simple instructions on transferring her feed to NuffnangX. I thought I would add the instructions I gave her, because the first one is a step by step of how to download your Google Reader feed data.
1. First you need to go here to Google Takeout and export your list of blogs https://www.google.com/takeout/#custom:reader. You will need to be signed into your Google account.
2. Then you press "create archive" which is a red button. A blue line will start. When that says "complete" in green writing, you can press "download" which is a blue button.
This will save a file to your hard drive. The normal way you save files, with a dialogue box asking where you want to save it.
Remember where you saved it and what it was called. It will say something like your Gmail address and .zip on the end.
3. Now go to your NuffnangX account and make sure you are signed in.
Click on your name on the right hand side. Choose "settings" from the drop down menu and it will take you to a new page.
On the left hand side of this page is a menu. The last item says "import subscriptions".
You upload the zip file the same as you would for putting an image as your profile on twitter for instance.
When that is finished you will get a list of the blogs you followed with Google. Tick the box next to the ones you still want and press "import selected" which is a blue button. All done!
Note: If you are new to NuffnangX you will need to create an account (you can log in with Twitter, Facebook or your existing Nuffnang account) and you usually have to pick at least one blog using their "getting started" prompts. Once your account is established then import the same as above.