We're in E9 and we had a hellava time trying to report on this. We ended up going down the following path:
We send the contact to a nonTrackableURL - this way we can exclude those click thrus from the Batch Overview Report. Prior to this approach, we were inflating our emarketing campaign metrics by showing a high click through rate for people trying to opt out of our marketing campaigns.
Then, we redirect to the Eloqua PURL Page to capture preferences. We pass the Email name (using the elqWAEmailName span tag) so that we can track which email is driving preference updates (and/or email opt outs).
Following is a sample of our footer:
<A href="http://www.nonTrackedURL.com/subscription.aspx?url=http://info.ihs.com/<span class="eloquaemail">elqPURLName51</span>%3felqPURLPage=311%26elqGUID=<span class="eloquaemail">recipientid</span>%26emailname=<span class="eloquaemail">elqWAEmailName</span>%26elqc=<span class="eloquaemail">campaignid</span>"><FONT color=#3390ff>email preferences</SPAN></A>\
Not sure if this will help in E10 - maybe you can use some of it?
Good Luck...