I've got an answer for this, or at least... I hope to have an answer, that is 'No'. But since I'm a newcomer with very poor experience in this wonderful world that is 'starting up', I'd like to have your feedback on this.
Italy is a difficult country for little software vendor startups for a lot of reasons including people mentality (except for some great ideas like balsamiq, prossimaisola.it, funambol and the mindthebridge initiative).
In my opinion, if starting up with a software product to be released using the Internet (as web app or also as desktop app) it's not so relevant from where you write the code.
Of course if you stay focused and if you aren't influenced by a negative ecosystem.
What do you think about that?
Yes and No. Why do you think there is universal answer?
In some countries it is easy for a lot of reasons but I think this should not stop you. And I live in a county where it was near impossible to be software startup before 5-7 years.
Have a look at past discussions:
http://www.brightjourney.com/q/best-geographical-location-business http://answers.onstartups.com/questions/3964/is-location-important-for-a-bootstrap-web-based-startup It will depend a lot on what your plans and hopes for the business are. If you're looking to build a 2-3 man shop via organic growth, then it won't matter much. If you're looking to build a 100 million $ company, then being in a creativity-dense environment with lots of potential for mentoring, idea building, and attracting capital is probably helpful.
Having said that, it probably doesn't need to be Silicon Valley. One of the new things is that a handful of cities now have good incubator programs loosely modeled after Y Combinator.
In terms of actually selling your product - I would say that location does not matter too much.
That being said, here are some issues that may matter...
To me, the biggest drawback is your ability to network with companies, investors and those willing to advise you. These communities SV, NYC, BOS, Boulder tend to have great atmospheres where you can network and really create some valuable relationships.
I would suggest you try to travel around and make some virtual connections -- this is what I am trying to do -- since I am in a similar situation (in Michigan).
You can definitely do it! The internet is a great equalizer.