Best Singers Today

This list from 2010 included:

Sopranos:

• Renée Fleming -- currently retired from opera but still singing.
• Natalie Dessay -- also retired from opera
• Anna Netrebko -- still at the top
• Angela Gheorghiu

Mezzo-sopranos -- all still active:

• Elina Garanča
• Cecilia Bartoli -- still going strong.
• Joyce DiDonato

Tenors:

• Juan Diego Florez -- has changed Fach
• Jonas Kaufmann -- still at the top?
• Placido Domingo -- no longer a tenor

Baritones and basses:

• Simon Keenlyside
• René Pape -- still at the top
• Bryn Terfel
• Dmitri Hvorostovsky -- has died

This new list reflects my biases:

Sopranos:

• Anna Netrebko -- still at the top
• Anja Harteros -- She's a star.
• Lisette Oropesa -- best candidate to replace Dessay
• Sondra Radvanovsky -- has achieved greatness.

Mezzo-sopranos -- all still active:

• Elina Garanča
• Cecilia Bartoli -- still going strong
• Joyce DiDonato -- she seems to shine brightest in Europe
• Anita Rachvelishvili -- any modern mezzo list must include Anita 
• Jamie Barton

Tenors:

• Javier Camarena -- best current coloratura tenor.
• Jonas Kaufmann -- still at the top?
• Roberto Alagna -- he's singing very well these days.
• Piotr Beczala

Baritones and basses:

• René Pape -- still at the top
• Bryn Terfel
• Ludovic Tézier -- he's been cancelling.  
• Željko Lučić
• No one really replaces Dima.