For lead generation:
The metric that I've been tracking more is new leads by acquisition programs.
New leads by source and geography.
I'm tracking new leads by paid ads vs. internal banner ads vs. content vs. social media
landing page performance and campaign performance.
For Publication/Newsletter, podcasts/video related emails:
I track opens, click-thrus, engagement (GA) & bounce rate. (I have to cross reference marketo metrics, GA and hootsuite stats and feedburner stats)
For web traffic: organic key words, unique page visits, visits/page, bounce rate, traffic sources, top 10 performing pages and content.
Deliverability stuff: Tracking invalid email, blocks and unsubscribes.
I report on the engagement metrics on the 15th.
First week of the month web metrics.
new lead reports on the first of the month too.
I report on our social influence on the first of the month.
I have to revise our goal metrics in Google Analytics and start working on retargeting.