I've create a couple of bug tickets e.g. http://open.silverstripe.org/ticket/5575 and checked cc. I presumed I would get an email when additions/changes where made to the ticket (similar to the Subscribe to this topic on the forums). I looked today and noticed that I didn't receive any notification emails after replies had been added. I check and the email address I entered does get delivered. Is there something I'm missing here (other than the emails :)?
Check the email address you have under preferences. I think it should use that email then when you want to be cc'ed just use your username. Also check your spam filter. I seem to be getting ticket email / updates fine and I think the only thing I did was put my email address in the preferences section.
Nothing in my spam box. I've changed the email to a different account, so I'll wait and see.