Here's my Feedly RSS feed made up of my go-to blogs for analytics knowledge: 

PPC / Paid Social:

1. www.adespresso.com
2. www.hanapinmarketing.com
3. doubleclick-advertisers.googleblog.com
4. adwords.googleblog.com
5. ppchero.com
6. wordstream.com

SEO:

1. searchenginepeople.com
2. searchengineland.com
3. searchenginejournal.com
4. semrush.com
5. screamingfrog.co.uk
6. seoroundtable.com
7. seerinteractive.com
8. searchwilderness.com

Ad/Tech industry:

1. Adexchanger.com
2. techcrunch.com
3. davetrott.co.uk
4. campaignme.com