Well there are several possible measures (and one very interesting candidate):
offline recognition (i.e. PR exposure, number of mentions in news articles), traffic/reach, (Alexa rank), popularity amongst Bloggers (Technorati 100), hybrid measure of online popularity (Google Pagerank).
The interesting thing is that there is no clear winner amongst these measures and that although there are similar rankings for top weblogs accross the board, there is one clear winner for Pagerank. It beats the Gawker media sites and Boingboing and Scripting with a Pagerank of 9 – PVRblog
PVRblog also has the biggest gap between Pagerank and Alexa rank. These stats demonstrate something interesting – perhaps PVR blog shows the perfect scope for a vertical market weblog with maximum Google exposure for its traffic.
I’m not entirely sure what this means, the difference should either disappear over time as a Pagerank of 9 drives more traffic and thus boosts Alexa rank – or if the potential readership is saturated, perhaps it will soak all the potential searches for PVR related content and pick up a large share of ad revenue with very good impressions to clickthrough rates on Adsense advertising.
I suspect the latter, that PVRblog is the perfect fit for a niche content site if you want to have targeted ad revenue.