Be careful with corporate bonds. JP Morgan's Chief US Equity Strategist, Thomas Lee, said corporate bonds could be the next bubble and "sees relative value of stocks verses their own corporate bonds" (video link). Treasury yields could have put in their 30 year low in 2008 (see post with 30 year chart and thoughts from Bill Gross, Jim Grant, David Rosenberg, who sees lower yields, on 4/5/2010). Yields move inversely with price. Also, Gregor Macdonald energy/macro analyst at Gregor.us and MacroTwits believes Treasury bonds have peaked (see MacroTwits hour 6/13/2010). Last but not least, "S&P Warns of Rising Corporate Defaults" - DealBook. Look at the chart of maturities.
"In 2011, there will be about $300 billion in debt due, of which 41 percent is considered speculative. But by 2014, the amount of debt due climbs to about $550 billion, 72 percent of which is speculative" [read more at DealBook].
hat tip wallstreet pit