Although my website target is global in its nature, most of the visitors of my site are from India. For some time as an experiment, I want to target India (Setting Geotargeting target to India in Google Webmaster Tools). Will this be a safe choice? Will it result in a tremendous decrease in google search result of my site for rest of the world?
I've heard that once your site is targeted to a specific country it can take a long time to reverse the setting if you decide to. If you are not concerned about any traffic outside India, I'd say give it a try and I'm very interested in an up-to-date report on how things go for you.
I messed around with Geotargeting this time last year. I targeted the US, specifically, and saw a decent rise in traffic from that region. Meanwhile my other key traffic areas (the UK most notably) dropped considerably and I decided it would be best if I reversed the change. I started seeing some change within 2 weeks after the setting but things never quite returned to 'normal'. We then had Panda to deal with and that brought a big unknown into whether things ever truly returned to normal. Currently the traffic from both countries is very good so I would like to say things returned to normal but would be interested to know how long it does actually take. If you decide to reverse this, in particular, I would be interested to know the timescale of change.
From my experience of working with some big Indian brands- if your domain name has a TLD .com but hosted within India then you can simply let the setting untouched provided that the site is a brand (gets good amount of brand traffic). As changing the target domain will not make much of the effect on traffic from Google India. Having said that, if your India vs non-India traffic is say 95%-5%, then you might consider changing the setting if the conversion rate is even lower/non-existent for non-India traffic as impact on final revenues will be negligible.