Some would say that less is often more. Less choices are better, less confusion and more direct.

However, your blog's subscription is one area that you should offer more choices in. This allows your readers to choose the best way for them to receive your content. 

The most commonly used option is a RSS feed, allowing readers to subscribe to all of your blog content via an RSS reader. This is a great option, but there will also be some that do not want to receive all of the content and just receive updates on specifics topics.  

WordPress makes it easy to offer your readers an option of subscribing only the specific category, or even tag, that they are interested in.

This all depends, though, on if you have set up permalinks or not. 

If permalinks are set up, then all your readers needs to add is add /feed/ to the end of the category or tag URL to get its feed. 

If permalinks aren't set up, then someone needs to add &feed=rss2 to the category or tag URL. 

See the following examples:

Permalinks: http://www.yourblog.com/tag/sky/feed/ 

Default: http://www.yourblog.com/?cat=2&feed=rss2

In fact, just about anything on your WordPress site can easily be converted into a feed. You can do this byappending the feed indicator to the URL. If you were to append it to your search results, you’d get the search results feed. If you were to add it to an entry’s permalink, you’d get the comments feed for that specific entry. 

Don't clut your blog, though, with several feed buttons.

Take the time to create a subscription page which explains the different options for subscribing to the various areas of your blog. Make sure you provide instructions for the different options too. 

Also,make sure that you update your feed buttons and links to mention that there are multiple subscription options.