"Whether, or not, a Greek exit from the Eurozone or a potential debt default is "the thing" that sparks the next major correction in the markets is unknown. Historically, such a widely "known" event is generally already factored into the markets and has much less of an impact when that event eventually comes to fruition. As Art Cashin suggested this morning:'I think China may be more important than Greece. Stick with the drill – stay wary, alert and very, very nimble.'"
1) The current bubble will eventually end, just as the last two have, in a rather disastrous plunge for those chasing returns.2) The plunge will also likely be coincident with an unwinding of excesses in the S&P 500.
Although Chinese equities have taken quite a hit, the manner in which they have fallen seems bullish in nature.