Sometimes droughts end with little fanfare, especially when bumper crops have sprung up without the rain.

Today, Developers Diversified Realty brought its much anticipated $400 million commercial real estate bond deal to the market, the first rain drop to fall in this parched market since last year. Moreover, the deal could be the first eligible for the Federal Reserve’s special lending facility, the TALF, which the central bank opened to new bond deals earlier this year.

The commercial mortgage market, however, has already improved substantially just on the idea that the rains are coming. Triple-A five-year risk premiums, at 440 basis points over swaps last week, are down substantially from a six-month high of 965 basis points, according to Barclays Capital.

Still, it’s going to take more than a trickle of new deals to bring the broader real estate market back to life.

It has taken months for Developers Diversified to pull together the deal, which involves just one loan backed by 28 shopping centers. Its long gestation helped undercut the “wow factor” when it finally hit the market.

Indeed, it may have been its simplicity that held it up. The Wall Street Journal reported last week that the Fed, which provides nonrecourse loans to investors purchasing commercial real estate bonds it deems eligible, was concerned that the lack of diversity made the deal risky.

The deal isn’t set to sell until November 16, which will give investors plenty of time to size it up. The juicy yields are sure to be tempting, as are the much more conservative loan-to-value ratios. According to IFR, the triple-A portion — by far the biggest piece at $323.5 million — could carry a yield of 20.5 percent and a loan-to-value ratio of 41.8 percent. 

If it goes well, it’s sure to be followed by more deals, but it’s unlikely to cause anything near the flood of issuance that helped finance the loans that will need to be renegotiated over the next few years. According to Barclays, more than $1 trillion of mortgages will mature by 2012.

The marked improvement in commercial mortgage bonds this year — helped by the Fed’s TALF program — has done more to throw a lifeline to underwater investors than to make a meaningful difference in a still depressed real estate market.

According to the Moody’s/REAL property index, prices are now 41 percent lower than they were at the peak two years ago. Such declines make refinancing extremely difficult.  And that means there’s a lot of rot to still root out.