Synology releases a new 2-bay NAS: DiskStation DS213+ that will replace the DS212+. When I think of it the DS212+ was not around for very long. It was replaced by the DS213+ after only 10 months. I do not know why it was replaced so fast, but Synology must have their reasons. My guess it that is DS2xx+ models are some the best selling models and in order to sell more Synology has put in more features.
The new NAS DS213+ has a dual core CPU, 512 MB RAM and is capable of having 2 hard disks with up to 4 TB data. If you have a DS212+ I see no reason to upgrade to a DS213+. I would not even upgrade my DS211+ to a DS213+. The DS213+ is not that feature rich so I skip an upgrade but I am still considering buying two Western Digital 2 TB Red hard disks that are made for NAS devices for my current DS211+.
My Synology DS211+ is now just a storage server.
I have moved all running services to my Mac Mini because some of these services is quite demanding and use a lot of resources and thereby leaving my NAS with to much load. I recently added 4 GB RAM to my Mac Mini so the total amount of RAM now is 8 GB which is perfect for a mini server. So I now have two servers: Synology DS211+ NAS and a Mac Mini. A perfect setup so far.
If you are looking for a great 2-bay NAS I would recommend the Synology DS213+ but if you have an DS211+ or DS212+ there is no reason to replace it with a DS213+. Unless you got a money tree or similar.