upgrading from older to newer versions

Hi guys,
I'm planing to put up a new website, of course I would like to customize look and feel of storefront. When new version 1.06 is released, what impact will have on my web site? Are pages completely separated from the engine?
Naturally, if I change any code (I saw some samples in other threads) those will be overwritten by upcoming release.

Thanks for your comments,
Ivan

Hi Ivan,
[quote]nopCommerce 1.05 will be the last version without migration scripts. All the next versions (nopCommerce 1.06 and higher) will be provided with migration scripts.
[/quote]

quoted from here http://forums.nopcommerce.com/forums/default.aspx?g=posts&t=34

Qais Afaneh