Font rendering: With flash you can embed fonts and have them render pixel perfect across browsers. Now with WOFF fonts (see google fonts, font squirrel, typekit) and CSS3 you can pretty reliably embed custom fonts in HTML.

Graphics: Flash was first of all a vector animation tool so this was its strong suit for many years. Now you can use libs like raphealjs, d3js, and fabricjs to render vectors with svg/vml or canvas.

I'll note that SVG could do much of this years ago, however IE not supporting it until IE9 pretty much killed its progress. If SVG fixed multiline text (it uses tspans to break up lines), I think it would be a better solution than canvas for rendering graphics and rich documents in the browser.