Comment 4 for bug 551580

As far as I am aware the standard 'incremental search' behaviour is to search on each letter including the 1st & 2nd letters. For examples see:

- http://www.google.com/webhp?complete=1&hl=en
- sending a new message on facebook
- searching in a browser using Ctrl+F
- Spotlight on OSX
- Instant Search in Microsoft Vista and Windows 7
etc...

(for further background wikipedia provides, see http://en.wikipedia.org/wiki/Incremental_search)

Although typing a single letter will rarely produce a useful result, the actions that are performed as a result of the letter being entered (moving selected contacts to the top left, highlighting the letter in names, updating the result count, etc...) start to give the user a 'tactile' feeling of the result set being narrowed. Different behaviours on the 1st and 3rd letters being typed would also make the experience feel very disjointed.