My first homebrew life was from 1990-1997, when dry yeast was absolute crap-- barely viable, often infected, no variety. Wyeast, and later White Labs, were the only options if you cared about quality.
My second homebrew life began in 2009. The single biggest improvement from then to now, in my opinion, is the quality and variety of dry yeast. I did my graduate work in a yeast lab, so I'm not afraid to make starters and propagate yeast, but given my druthers I'd rather avoid it (seems too much like work!). Dry yeast is perfect for me, unless I need something specialized-- then I'll likely go for White Labs with a starter.
I use US-05 and Nottingham most often, but I want to give a shout out to the rarely mentioned K-97, which I love for German-style ales. I'm interested to try the dry Belgian and Weissbier strains this year.