First, yes, there is a reason to migrate - DNN3 will come to an end of its life cycle soon and further developement will take place only with DNN4+. BEsides there are security issues, that make it advisable to upgrade to the latest version.

After I did a number of migrations from DNN 3 to 4, I can tell you, that upgrade is not very difficult. The warning of y01nk is valid for source code only, so please make sure, that there is no .vb o .cs file in your installation, before unpacking DNN installation or upgrade package.

y01nk,

I don't think, there are no difficulties on an upgrade, but an upgrade from 3 to 4 is not more dificult than any minor one, there are only 2 additional pints to take care of, as I stated previously. There are many people reporting upgrade issues - most of them for minor upgrades and the majority did not read carefully the upgrade instructions (the others have inconsistencies in their installation and we try to asisst them here as much as we can!).

Regarding life cycle, with software, and especially web software, it is important to stay up to date

- due to developement of platform technology and client software (e.g. IE7)

- for security reasons (there have been detected issues for several DNN releases, that have been fixed in the latest one.

- most current core and 3rd party modules are developed against current DNN version and operate only on current versions.