While the discussion about Bitcoin Core vs. Bitcoin XT carries on across the world, various mining pools have already implemented the block size changes proposed by Bitcoin XT.
No. A few P2Pool nodes and Slush's pool (as an option). Maybe more, but so far only Slush's pool have produced blocks (3 of them so far) with the necessary block version in the header.
Judging from the latest BlockTrail API statistics, multiple “XT” blocks have been mined on the Bitcoin network, all of which are 8 MB in size. Is this a sign of things to come, or just a flash in the pan?
It's a sign of misinterpreting that page. The ones labeled '8MB' at
https://www.blocktrail.com/BTC are votes via the coinbase scriptSig, and should be considered at best a BIP100 type vote, and at worst just a sort of public statement that they'd be okay with 8MB blocks.
"A large portion of the Bitcoin mining community — roughly 75% — has shown indications of being in favor of switching to Bitcoin XT and 8MB blocks as of January 2016."
No. They have shown indications of being in favor of 8MB blocks; some of which reluctantly. Most of the Chinese pools (referenced further into that article) in fact have noted that they're not in favor of XT;
http://cointelegraph.com/news/114657/chinese-mining-pools-call-for-consensus-refuse-switch-to-bitcoin-xtOne recent statement from Antpool -
https://twitter.com/JihanWu/status/633288343338381314 - notes that IF a majority has switched, they would switch to XT as well. That's not a statement of support, but one of economic realities as they perceive them.
One would hope that a media outlet that focuses on Bitcoin would get these things correct.
