Below we briefly review two of these services, Apture and Zemanta's Balloons. Is this kind of product really worth using? Once you add a pop-up of someone's LinkedIn profile next to their name as you type it, you may never want to go back to not having a tool like this at your disposal.

Apture

We started by testing out Apture's WordPress plug-in (on my personal blog) and were very happy with the results. It takes just a few minutes to install, and learning to use it is quite intuitive. We wrote an extensive review of Apture in February.

Pros:

• It's beautiful. From the admin section to the pop-up windows, design has been emphasized at Apture.


• Lots of user control. The amount of control users have over what's included in their pop-ups is amazing. You can choose between assets with a few clicks, or you can pick out start and end timestamps in an embedded YouTube video. The list of options is big and keeps getting bigger, as evidenced by the recent addition of really nice LinkedIn and Twitter profile options.


• You can now include multiple tabs in one link, making it easy to pack a lot of information inside.


• The user experience is solid, and the product is pretty well baked.

Cons:

• Apture is proprietary software offered by one company, unlike Zemanta's standards-based offering, which was built as part of a consortium of developer- and community-minded companies.


• Sometimes it hangs on the UI. We found one bug that the company has since fixed, but pop-up loading is sometimes slower than we'd like.

Zemanta

Zemanta is a feature-rich service for bloggers and has a great API that developers can use to automatically discover keywords in bodies of text in lots of different scenarios. You should check it out. It's quite easy to use. Last week the company released a feature that competes with Apture, called Balloons. Balloons is now automatically included in the blogging plug-in from Zemanta, which is very easy to get started with.

To be frank, we would recommend installing the core Zemanta plug-in for the rest of its features but using Apture for info pop-ups instead. The way the two products are administered is very different; Zemanta detects key concepts in the text of your post and suggests Balloon links you can add with a click. You're limited to adding just those handful of Balloons; you can't link up just any text you want.

Pros:

• Zemanta is open source and standards-based. It feels good to use.


• Zemanta works with the rest of the tech community and has some awesome tools for supporting non-profit organizations. Did we mention that it feels good to use Zemanta?


• The auto-detection of key concepts -- just click on the buttons and they're linked to resources -- makes Zemanta a little bit faster to use than Apture. It takes fewer clicks.

Cons:

• This tool isn't nearly as pretty. In fact, the pop-ups are almost the opposite of pretty.


• You have far less control over the sources of information you can include. Zemanta's Balloons is tied to the ambitious CommonTags standards effort and apparently does not include anything outside the world of standards. That's noble but limiting.


• Most of the links Zemanta inserts are to FreeBase, which is like a machine-readable version of Wikipedia but also a noble, well-funded mess. Thus the pop-ups you get from Zemanta are quite hit and miss.


• There are Amazon affiliate ads in the Zemanta product; Apture's business strategy appears to be to serve bloggers for free and ad-free and charge big publishers to white-label the service. Zemanta's Amazon ads might get on your nerves.


• This is a very early product, having just launched last week. We hope it is further developed.

That's our experience so far with these tools. If you've tried either or both, we'd love to know about your experience as well.