Eric Sink has announced the SourceGear release of DiffMerge 3.1. Killer feature for me is the correct TortoiseSVN merge command is now documented in the help, copied here for your pleasure:
/m /r=%merged /t1=%yname /t2=%bname /t3=%tname /c=%mname %mine %base %theirs
Fantastic. I’d still love to see all four views at once (theirs,base,mine,merged), but this help makes the product very useable now for conflict mergers.