These WordPress plugins add non-frivolous functionality, executing or helping you to execute complicated tasks faster and better.
Simple Trackback Validation
Catching comment spam is pretty easy and effective with the Akismet plugin but doing the same for trackback spam seems virtually impossible.
Trackbacks appear in your comment stream when another blog references one of your posts. The text of the link and of words surrounding it appear with [...] square brackets around it in the admin section of your WordPress.
As with regular comments, each trackback moderated and allowed through turns into a backlink of small importance to the site sending the trackback. Collect enough of these, as a website, and they can help you rank.
And that's where trackback spam comes in.
Trackback spam comes in two forms. One are trackbacks from scraper sites. Stealing the post from a legit blog that referenced you, their republishing of the scraped posts means repeated trackback requests. And each one that you allow helps build up the ranking of that scraper site. The second form of trackback spam is where a script sends all the information needed for a trackback link but your post was never referenced to begin with. These type of scripts can build such links for any site they plug in; no need to actually quote any post from anyone, anywhere.
While comment spam is often easy to catch because of the low value/high nonsense ratio ("Good post valuable yes"', "I the we no topic used Ford", etc), trackback spam is much more laborsome to weed out. A couple of trackbacks can be discarded right away based on their domain name or because you remember the original link it comes from. But 8 out of 10 trackbacks require you to visit the link -- with all spam malware risks associated with that.
The Simple Validation Plugin changes all that. It performs 2 basic yet highly effective tests
1. Does the IP address of the sender of the trackback match the IP address of the domain the trackback claims to be from?
Most automated trackback spam scripts don't run on the same machine so this test already weeds out the majority of trackback spam.
2. If the IP address and domain name match, is there an actual link to your post on the page? The plugin will fetch the page doing the trackback and validate that this is indeed the case. If not, no link.
As a bonus the plugin will also prevent trackback requests coming from topsy.com
ManageWP Worker
The more WordPress powered sites you run, the more time is lost on doing maintenance and upgrades. Even when you run a more or less standardized install, doing on of WordPress' many regular updates and upgrades can cut into your work time.
Manage a blog park for your company's clients and you're looking at hours of wasted time.
ManageWP Worker makes working with and on multiple blogs not only possible but easy simple and smooth too.
The free plan (good for 3 site, or 5 if you refer some folks) let's you upgrade WordPress, plugins, and themes all from one central login. You can install and activate plugins and themes just as easy as you can add posts and pages; again, all from one and the same point.
Jetpack
Jetpack adds 10 free features and 1 optional premium one.
To pick the 3 best or most interesting features to highlight: stats, new shortcodes, and awesome spelling and grammar check.
Stats: easy, clear, concise visitor stats that show you -- to the point -- what's going on with your blog. Runs off the WordPress.com servers so it doesn't out a load on your own installation at all.
Shortcodes: embed YouTube, Vimeo, Flickr and more with simple to use [shortcodes]. You can type them or click the new buttons.
After The Deadline: artificial intelligence routines help flag spelling and grammar errors in your copy.
Conclusion
While Simple Trackback Validation does one clear-cut task and does it well, ManageWP Worker and Jetpack do a bunch of smaller and bigger tasks. Take your time to evaluate them, perhaps on a test blog.
What plugins would you recommend? Got any favorites?
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