Esse tipo parece funcionar. Eu não tentei ainda.
A essência disso é que existe um arquivo CSS padrão que o Chrome carrega. Você pode definir seu nível de zoom lá. Melhor ainda. Se você executar um zoom manual, o Chrome se lembrará desse site.
link
edit: oops, esqueci de colar as instruções ...
Chrome loads user-defined stylesheets from the ‘User StyleSheets’
folder. In Linux, this folder is usually located in
‘~/.config/google-chrome/Default’. In Windows, this folder is in
‘%USERPROFILE%\Local Settings\Application Data\Google\Chrome\User
Data\Default’ for XP and
‘%USERPROFILE%\AppData\Local\Google\Chrome\User Data\Default’ for
Vista and above. Chromium has slightly different folder names [2].
There should be an empty Custom.css file in the ‘User StyleSheets’
folder. Just add the following lines to the Custom.css file and save.
1 body 2 { 3 zoom: 1.5; 4 } Styles defined in Custom.css will be
applied to all websites visited. The above lines will automatically
zoom every website to a pre-defined level of 150% (=1.5). In cases
where 150% is not ideal and manual zooming is used, Chrome’s built-in
zoom-memory will kick in and on subsequent visits, zoom the content to
the manually set level instead of the pre-defined 150%.
In short, four lines of code, along with Chrome’s built-in features,
pretty much achieves the basic functions of NoSquint on Firefox:
default zoom level plus site-specific zoom level.
[1] http://userstyles.org/
[2] http://www.chromium.org/user-experience/user-data-directory