If you are a fan of Growl notifications on your laptop, then you'll love NotiPad on your jailbroken iPad. NotiPad will replace banner style notifications in iOS 5 on your iPad with the very nice UI of Growl notifications on the Mac. In NotiPad within the Settings App, you can change the animation style and location for incoming notifications. There are also toggles to further customize NotiPad.
check out a short video preview of NotiPad:
NotiPad is for the iPad (even though it may read "Not iPad") and is expected to run $1.99, check out Cydia on your iPad in the next couple days for this new tweak.