Depends on the weather. In a dark, murky day everyone has their head down minding their own business. However, for example it is the first day of spring (even here in dreary Scotland), the sun is shinning, the snowdrops and crocuses are out and you feel just wonderful to be alive then with a spring in your step it is likely most people will say to those passing in the street something like "Good morning!, "Lovely Day","Seems like spirng is here" or something similar.