Google Gmail already optimized for Apple iPad
Apple iPad users can access Gmail through a special interface specifically designed for this device.
You can play around with it right now by using this text as your user agent:
Mozilla/5.0(iPad; U; CPU iPhone OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B314 Safari/531.21.10
The interface is of course optimized for touchscreen displays though it works fine with a mouse.
You might want to play around with it as your default interface if the regular Gmail user interface is boring you!