1GB is fine for me for ordinary software work - but i almost never use IDEs or other large tools.
An employer ought to provide 2GB, don't care about clock speed (yeah, faster compiling is nice, but 91% of my time is thinking, reading, etc), two monitors. Gotta see code, ref material, debug output, and the program's windows (if it has any) all at once. Most important: an ergonomic keyboard with touchpad. Or some decent keyboard; i can adapt if it's designed well.
If i were the employer: crappy squeaky abacuses with loose rusty wires from the competitor's dumpster! Ha ha!
Seriously, i'd ask and provide, with the default being same as what i'd expect, described above. But i realize i'm an imaging/photography/graphics expert, not an average geek,
For myself: any laptop with 4GB, 17" screen, good keyboard, 3 USB ports or more, HDMI plug, CPU irrelevant. I've not used my desktop machine in 3 months. Yeah, a graphics expert ought to have 3 huge screens and a power CUP, but i love working at the coffee shop, in the living room, etc and often can't work at home.