Once again we round up six of the best infographics we’ve seen this week.

The topics include how to optimise mobile landing pages, big data, why email still matters, the top 1,000 YouTube channels, Facebook at 1bn and eBay’s 100m mobile app downloads.

Top 10 mobile landing page tips and best practices (Ion Interactive)

Are retailers ready for big data? (Baynote)

Why email still matters (Eloqua)

The top 1,000 YouTube channels (OpenSlate)

Facebook at 1 billion (KRDS)

eBay celebrates 100m mobile app downloads