If you use Hotmail (including Live) to your e-mail and want to get Android on your mobile, you should probably use the native mail client available in your device.
The problem is that Hotmail offers only two standards for connecting to the service: POP3 and DeltaSync. POP3 is a protocol rather old which does not allow a real sync, your messages are only downloaded, for example, your e-mails « read » are marked as such.
Hotmail does not support IMAP protocol because Microsoft offers DeltaSync (owner) to completely synchronize the services associated with Hotmail and Live, but this protocol is rarely supported by the apps, except those of Microsoft.
A formal application for Android Hotmail has just made its appearance on the Market, the messages come in push, contacts and calendars are synchronized, you can add multiple Hotmail accounts and send / view attachments.
Based on initial feedback, the application uses a lot of battery and the interface could be reworked but still well done the job.