The first tweak is via an experimental user interface for Gmail based on the HTML5 mobile web app developed for the iPhone and Android. It will feature a two-pane view with a conversation thread listing on the left and message pane on the right (screenshot below), according to Mashable.
It was also announced that several Google services will ship pre-installed on the iPad as apps.
Just like the iPhone, the iPad will have a YouTube app, but in this case, it will support HD viewing and commenting. Additionally, the Maps app utilizes high-resolution imagery from satellite and Street View, and includes a new terrain view.
As with most mobile devices, Google is the default search engine in the Safari browser. It will also be able to use the Google Mobile App with voice search, but it has to be downloaded from the App store as it won't be immediately available on the device — similar to the iPhone.