I am member of Orkut and I don't like when someone scrap me or send me a message advertising their products. I've also joined many communities in Orkut where many people advertise their products which I also don't like and I'm sure other people won't like this too. You can also get into trouble with your affiliate programs (like Google Adsense) as it is closely related to spamming.
If you find people relevant to your products and if they are really interested in it then there in no problem in promoting it via orkut or facebook ... You must join relevant communities as well then there is no problem in promoting your product or website .. People really scrap me back if they view my web and get attracted to it and i don't think so they get irritated
