Thanks Steady, I'm always interested in new ETF ideas (tend to avoid ETNs though as apparently they add counterparty risk).
You might be interested in checking out IndexUniverse's ETF Watch newsletter (can read it online, sign up for email alert or follow on Twitter):http://www.indexuniverse.com/sections/etf-watch.htmlhttp://twitter.com/#!/IUETFWatch
It's a weekly snapshot that includes new ETFs listing, filings and closures.
I tend not to pay much attention to the filings as there seems to be a million ETF filings many of which will never see the light of day or might not for some time, so I just keep note of the ones that actually list and add them to my watchlists where interested.
You get a lot of ETF closures, as the ETF backer throw everything against a wall just to see what sticks it seems.
Another good source of info is Ron Rowland at Seeking Alpha, who writes about ETF comings and goings, including a monthly ETF Deathwatch:http://seekingalpha.com/author/ron-rowland/articles
I'll come back and peruse this list when I have more time as looks like a great resource.
Don't have much to add otherwise off the top of my head other than to say you can do very well with the leveraged ones. I held AGQ for two months early last year and doubled my money (also doubled my money in PSLV, but it had taken six months). They say leveraged ETFs are for short-term in/out trading and shouldn't be held over time, but seems to me it's only if the trend goes against you that you get burned.