I was looking for a plugin to create a smart location form field which has a suggested autocomplete. I was unable to find anything suitable (Google Geocode is too unreliable
What is your data source of locations? If it is geonames.org, they have different geographies on different servers - with different performance characteristics. Hence it is common on a worldwide search to see jerks, odd responses, etc. as different servers toss back at different times. I found that user selection of a country, and feeding that into the city query pretty much eliminates jerkiness, odd responses, etc. If you are using geonames.org, they require attribution at the search box. If you are using a google data source of names, I can't comment, but you might check how they handle major versus minor countries. Also, think about the level of detail provided. Geonames is remarkable on that score.
OSClass.org provides its theme for free which has location autocomplete with all areas being populated automatically. This you can check in their demo and download the code from within their theme files. Demo (login and go to Settings->location section) : http://demo.osclass.org/general/oc-admin/index.php?page=login
There is a widget that does that, the jquery ui autocomplete.
http://jqueryui.com/demos/autocomplete/#remote-jsonp
This demo is exactly what you need, selecting locations over the world
Hope this helps. Cheers
Check out this one Download http://code.google.com/p/geo-autocomplete/ Demo : http://geo-autocomplete.googlecode.com/svn/trunk/demo/ui.demo.html
If the problem is related to the highlighting you might want to check the success section of your ajax call and make sure that you are un-highlighting in the right moment. Because the section is always changing it might glitch at one point given the nature of bringing back lots of info and altering dynamically
hope this helps!
ps. autocomplete jQuery will autocomplete anything it feeds from