Perhaps the most anticipated new feature in FeedDemon 2.0 is its ability to synchronize with NewsGator Online, enabling you to keep your subcriptions - and unread items - synched between multiple computers.
So far we haven't documented FeedDemon's synchronization very well, in large part due to the fact that it's still a work in progress (FeedDemon 2.0 is a beta, after all). But I've noticed some confusion as to how the synchronization works, so I wanted to take some time to explain it better.
FeedDemon enables synchronization at the folder level, so you can choose to have some folders shared between all of your locations, and others private to a specific computer (in my case, I don't synchronize folders that I only need on my primary desktop). To enable synchronization for a specific folder, just right click on it, choose "Folder Properties," then place a checkmark in the box labeled "Synchronize this folder with NewsGator Online."

After enabling synchronization for a folder, it will be added to NewsGator Online and all of its feeds will be available from any computer you use. Any feeds you add to this folder will automatically be added to your NewsGator Online subscriptions. And when you read an item in one of these feeds, it will automatically be marked read in NewsGator Online - so items you read in one location will remain read on any computer you use.
At this point, I should explain an important sync-related setting that you might not be aware of. If you click the "Synchronization" button in FeedDemon's options, you'll see the dialog shown below:

Note the checkbox labeled "Retrieve only unread items in synchronized folders" - this unassuming option actually has quite an impact on how synchronization is handled. By default, FeedDemon will only retrieve unread items in synchronized folders. This cuts down on bandwidth consumption, since items you've already read aren't re-downloaded. However, a side effect of this option is that items you've already read in NewsGator Online won't automatically be marked as read in FeedDemon if they already exist as unread in FeedDemon.
For some people, that's no big deal - for others, though, this is a big problem. We've heard a number of people complain that synchronization in the FeedDemon 2.0 beta isn't working, and the culprit has invariably been this single setting. Because of these complaints we're rethinking our approach to how unread items are retrieved, so this shouldn't be a problem by the time FeedDemon 2.0 is out of beta. In the meantime, though, if sync isn't working the way you expect, try disabling this option.
You'll also notice the option to check for subscription changes when FeedDemon starts. When this is enabled - which it is by default - FeedDemon will check whether any feeds or folders have been added to (or removed from) NewsGator Online since the last time you ran FeedDemon, and if so, you'll be asked whether to apply those changes to your FeedDemon subscriptions. I recommend leaving this option enabled, since it makes it effortless to keep your subscriptions synchronized.