Going back to India.

[NANC]

Hi Friends,
I am returning back to India this july.
I may come back to USA after few years.

My 7th year visa expires on Oct. 2008. (I have notice of approval I-797)
I have not stamped 7th year visa on my passport.

My question is:

For future purpose:-
Is it wise/useful to get 7th year stamped on my passport once I return to India.
OR
it dosent matter.....

Thanks for your help.

-nanc