Live Tiles are consistent, with only three square (rectangular) sizes to pick from. The fluid scrolling through them (rather than page by page) makes it feel more spacious. I have an entire home page dedicated to Facebook, for example, because the Facebook widget that shows me updates (and only one update at a time) takes up fully half the screen. The weather widget I use takes an entire line of icons, and the calendar widget takes up two columns by three rows. It's like playing a jigsaw puzzle trying to arrange a useful "live" home screen. Live Tiles are also visually consistent, which Android widgets are not (my Android home screen looks hideous).
A Live Tile is a app shortcut that also acts as a widget by displaying useful information. An Android widget is a widget that can also link to the application. That tiny difference is a huge gap in comparison.