I've been a fan of Google Suggest since I first saw it - and I think that the news that it will now become the default experience for all Google searches is very significant because it will change everyone's expectations of what should happen when they start typing into a search box everywhere:



Of course several search boxes already do this kind of thing (the search box & 'awesome bar' in Firefox 3, the 'omnibox' in Google Chrome) but I believe that its use will become widespread not just for web based searching but also within desktop applications.

In 2005 just after Google Suggest came out I implemented my own version of it - it doesn't take much to get the basics right - you just need a reverse index. A bit more work and some stats can help eliminate common 'stop words' & give spelling suggestions; some further work and you can index two or three word phrases. Some of this stuff ended up in a desktop product in my day job.

Of course in a disconnected desktop product one doesn't have the huge amount of statistical information on what is searched for & clicked on, but to get a simple version of 'suggest' up and running can be quite quick and gives the user real tangible benefits.

The search box _should_ never be the same again...

What are the goals of visualization? And what are the features that support those goals?

My 10 cents worth:

The basic goal is to facilitate reasoning and thought about what is being visualized. That reasoning could revolve around causality, hypothesis, predictions, inferences, habits, modus operandi, contradictions, uncertainty, and a whole host of problems the user is trying to solve. Often the reasoning revolves around external data and/or knowledge too. Visualization should expose structure in the data such as patterns, clusters, gaps, bursts of activity, outliers & trends, etc. And at the end of the reasoning process the great thing about visualization is that one should end up with a picture that can be used to disseminate one's insights to other people.

So what key features enable these goals to be achieved?
* A Summarization/Overview to give the big picture
* Zoomability
* Drill-down on data for the detail
* Easy navigation around the visual
* Filtering information by category or query
* Different types of visualization expose different patterns (geographic, timeline, textual, lists, link diagrams, etc.)
* Brushing & linking visualizations together can help the filtering & exploration

Other basic things which must be in place in order to succeed:
* Ease of import and export - and adhering to any standards
* Some basic searching of the data
* One must be able to read the data - in particular any text
* Scaling well as the data size gets very large
* Links out to other systems for further information is key
* Links back in to the visualization from other systems can also be powerful
* Interoperability with other visualization tools and other applications in general
* Commentary, scribbling and drawing on the visualizations is a great way to add understanding - a picture alone is rarely enough

And don't forget the more esoteric things too:
* It needs a positive emotional response so it must look good and not conflict with user's expectations
* It can use standard visual symbolism, conventions & metaphors
* It must use the basic visual variables well (shape, colour, position, etc.)
* Transitions between visualizations must be smooth to allow the user to keep their context
* It should use design techniques like 'information scent' & obvious affordances
* It should facilitate playfulness where ever possible - don't punish 'mistakes'!

Phew - glad I got that off my chest - back to the day job :-)