One of the things that is really important to me is making sure working on Windows and Windows Live is a low-stress job.  Stress is evil, in fact stress is defined as:
stress: strain felt by somebody: mental, emotional, or physical strain caused, e.g. by anxiety or overwork. It may cause such symptoms as raised blood pressure or depression.
The thing about stress is that it is both physical and emotional.  Stress is all about a loss of control (anxiety).  Loss of control comes from not really knowing the goals, not understanding what success looks like, and in our vernacular, about being random. Stress comes because the work required is incompatible with your capabilities or your view of success.  Stress is about a mismatch between your reality and the reality of your manager or team.
Stress in the workplace is 100% incompatible with building great software.
On the other hand, pressure is all around us.  We have pressure to succeed.  Pressure to get the build right.  Pressure to get the design right.  Pressure to go live with content.  Pressure is a motivator.  Pressure is defined as:
pressure: urgency, as of affairs or business
The thing about pressure is that it comes from within.  Pressure is about the plan.  Pressure is about your own goals (affairs).  By operating with a plan and the details of that plan were created by the team we transform what might be stress into pressure.  Pressure comes because you want to be successful against the goals you have set out.  Pressure comes because the peers you depend on are expecting you to deliver what was communicated.  Pressure is about the constant force in our environment to deliver on the plan we developed together.
Pressure in the workplace is how we stay on our toes and put forth our best efforts.  Performing under pressure, while challenging, is what helps us as engineers to make great choices and use the constraints to our (and our customers) advantage.
No one works well under stress—the physical toll is real and provable.  Some folks don’t work well under pressure.  You don’t have to put yourself under pressure, but we’re a competitive company and like a great athletic team we do want that effort to go above 100%, but we can do so in a constructive way by using pressure to our advantage.
We’ve got some pressure going on now on our team.  IE 8 in the final milestone.  Integrating the M1 build of Windows Live.  Windows 7 moving to M3.  We’re excited.  The pressure is real.  It is pressure like being in the World Cup because we know what got us here and we know what it takes to be successful.
—Steven Sinofsky (@stevesi on Twitter).
PS: Yes these words are similar.  The beauty of words are the subtle differences that make them special.
PPS: I’m just excited to use the new build of LiveWriter – and the whole Wave 3 suite!