OK, OK, I've tried to avoid the ensuing over-panic about "swine flu."

From my school's dean, a pulmonologist:
Masks over the healthy do NOTHING. Viruses are small enough to pass through the pores. Since you need to touch the virus on a surface, or breath it in, just wash your hands.

Masks over the SICK make sense: the virus is in the droplets that they sneeze and cough up. Block the drops, you keep it better contained.

Remember, N95 masks block Tuberculosis - still way, way bigger than a virus!

Various news bulletins from the FD I volly for suggest this is still not much of a "panic" bug. Really, the death toll from regular old flu is 36K annually in the US. This is, what, 1 in the US to date? Does it have the potential to reach 1918 levels? Maybe... but we have Tamiflu which helps decrease duration of disease, as well as symptoms.

As one of the CDC officials pointed out, the reason we're "seeing" more cases as the days go on is that we're now testing folks for it. By looking for something, we're finding it. That doesn't mean we haven't had swine flu in the US before, it's just that we didn't look for it. The normal "flu" swabs that most docs use just test "a" or "b" strains. Swine flue is still in the "a" category, so it's entirely possible we've been treating it like any other strain.

Personally, I'm not worried just yet, until the death toll starts to get higher (in proportion to number of sick). Avian flu/SARS seemed a much bigger threat.

Edit: Having said all this, the EMS guidelines I'm seeing currently are recommending N95 masks, gloves, gown, eyes for CONFIRMED cases only. Otherwise, suspected cases are still OK with gloves, eye shields, and surgical mask only if close contact is anticipated during procedures. Then just wash hands before and after.
http://www.cdc.gov/h1n1flu/masks.htm