SignalTap II or In-System Sources Probes Editor

is Sources and Probes really that new of a feature? to me they have slightly different applications.

Sources and Probes is great for board bring up to toggle outputs and read inputs without writing any HDL (besides a port map). it is also useful for emulating push buttons or similiar signals

SignalTap is "read only" but has simple and complex triggers. it can buffer a large amount of data which is then read out by JTAG which is really useful for in system debug