As you noticed there are frequent maintenance releases of Symfony2, the 2.0.10 version is already out. To avoid doings thing manually I use this simple bash script to make the update: (It works with a Symfony2 standard edition). To use it, just launch the script at the root of your project: (be careful as it will delete your vendor directory)
./update_symfony 2.0.10
The bash script:
See you. 
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