Grey! Sherwin Williams Repose grey is a very popular one!
Hi Lynn: Do you want popular or something you can live with for about 10 years? I'm sure you don't want to be repainting every couple of years:) You can always paint 3 walls a neutral colour and then paint one the popular colour. Paint whatever makes you happy:) Good luck
Why follow trends - pick a color or colors you love and be yourself. I would only worry if you are planning on selling in the near future.
Neutrals are the most popular. For versatility go with a greige.