I saw many question addressing this issue but still i have some doubts…
I followed the steps given by Chris Smith in this question
- Increase the value of the
android:versionCodeattribute of the<manifest>element in your AndroidManifest.xml - Build, sign, zipalign the apk as you did originally
- Go to http://market.android.com/publish/Home
- Click on the app name
- Click on
[Upload Upgrade]
But no where i could found [Upload Upgrade] option in developer console as he told.
Please see the image below 
Anyone knows what was the problem?
Google changed the upgrade GUI so the post that you are referring to is no longer valid.
From your screen