As far as I understand, the Django app you used has different functionality from Wordpress, so not sure how much this benchmark is useful?
How caching is implemented on each app, how much I/O access the URL you benchmark requires (esp. session, which IIRC may fall into race condition in ab-type benchmarks) can make a huge difference (also IIRC - PHP should perform significantly better as Apache module than under FCGI)
Ultimately it's really an app comparison, I'd guess PHP or Python have relatively little impact on the results. Find a Django app (or RoR, or even another PHP app) that gives you everything you need from Wordpress, benchmark and you'll have useful data.
WordPress is really inefficient query wise out of the box. The caching stuff really speeds stuff up, but there's no reason why a fresh install takes 20 queries to load a post. Add a few fun plug-ins into the mix and you can see why WP sites often take a dive when hit with unexpected traffic.
How caching is implemented on each app, how much I/O access the URL you benchmark requires (esp. session, which IIRC may fall into race condition in ab-type benchmarks) can make a huge difference (also IIRC - PHP should perform significantly better as Apache module than under FCGI)
Ultimately it's really an app comparison, I'd guess PHP or Python have relatively little impact on the results. Find a Django app (or RoR, or even another PHP app) that gives you everything you need from Wordpress, benchmark and you'll have useful data.