The Android app has its own fair share of troubles though. It's not very good in actually receiving the email. The email it gets is fine, otherwise though it has to "sync" everything. I can't just turn on email syncing and get my emails in a PUSH way, it's still delayed. When I press update it generally takes 1-2 minutes over 3G to actually update.
Check, if the Settings | Accounts and Sync | your gmail account | Sync Gmail setting is turned on. If it is, the Android app has no problem with push email. It has worked for me since G1.
