Editor's note: Data from Realtor.com's first-quarter real estate trend data report. The report analyzes data for 146 U.S. metros and includes single-family homes, condos, townhomes and co-ops. The spring homebuying season continues its brush with optimism with median list prices of homes for sale nationwide up 5.56 percent over the last year, according to Realtor.com data updated through March 2012. The jump to $189,900 brings the national median list price close to what it was two years ago.Continuing a distressed-market turnaround trend, the Phoenix-Mesa, Ariz., metro took the No. 1 position on the list with a 23.5 percent jump from a year ago, to $179,000. The Miami metro made No. 2 on the list with a 22.27 percent list-price increase from a year ago, to $269,000. Both Phoenix and Mia...