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These may not be the best or my favourites, but I certainly use them every day:

Instapaper
Flipboard
Evernote
DocScanner
TV Guide
 
Facebook
Around me
Evernote
Taskflow
Dropbox
Shazam

it's top 6, ok, but I couldn't exclude facebook :D
 
There are exactly 5 non-Apple apps on my main screen:

NightCap
SkySafari
ProCamera
MediaTransfer
Waze

Honorable mention, however, must go to a combination of two apps:
Photosynth and TinyWorld
 
Pages

Facebook

Tunein

Safari/atomic wb

imdb

khan academy

tower madness

its 7 now but i couldn't get it less than that
 
My 5 top apps

- Paper by 53 : drawing app
- Pulse : RSS news reader
- OPlayer HD : read video stored on local network without server software
- Memory (link) : Memory-like game my kids love it
- Shazam
 
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