If you're still having trouble with Chrome or Firefox, please reply below with your browser and version, and possibly with a gist/pastebin of any console errors. Mark and I will get on it.
Regarding the lag: We match you with players based on your latency to each gameserver and the amount of time you've been waiting. If you experienced a lot of lag earlier, it might have been due to there being too few players online. However, 196 people are playing as I type this now, and hopefully there's now enough player density so you'll get matched with a lower-latency player who's nearby.
You can read more on our blog post: http://blog.artillery.com/2012/10/play-powderkeg-html5-multi...
We're also on VentureBeat today: http://venturebeat.com/2012/10/04/artillery-aims-to-make-web...
Also, I'd like to thank our amazing artist, Adam deGrandis. Check out his portfolio — he's incredible: http://www.adamdegrandis.com/portfolio/
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