Question:
It's simple!
1.
Scrub your windshield -- and I mean climb up there and scrub it -- with a clean cloth/rag and a cleaner/detergent every couple weeks. Tiny bits of oil or diesel fuel just get smeared around with fuel island squeeges, and form a base-coating on the glass that combines with wax and turns into a micro-thin glaze on the glass -- even when it "looks clean".
(Note: Always "scrub" your glass with a NEW towel, sponge or cloth. One tiny grain of sand imbedded in a sponge, for example, can leave swirling scratches on glass when you're really "scrubbing" it hard. A soft sponge and some dishwashing liquid work just fine, but make sure you're opening a brand new sponge out of it's original plastic wrapper.)
2.
Buy new wiper blades!!!!!! And I MEAN IT!!!!! Install new ones every couple months. That's right, every TWO MONTHS!! Your wiper blades get as much wear and tear in two months, as a typical car's blades get in two years!
(if you're a company driver, you get them for free anyway. It's well-worth climbing up there and clipping on new ones every few weeks.
Winter driving is hard enough. Don't be "penny wise" and safety foolish by trying to see through a smeared windshield. If your glass is really clean -- scrubbed clean -- and you have fresh wiper blades, every pass of the blades will produce a perfectly dry/clean piece of glass to look through.
"Rain-X" works well if applied to a clean windshield. Just remember, it is a "wax" -- softer than the glass -- and oil/dirt will get rolled into it over time. Best to clean it all off every once in a while and start over. Otherwise, "Rain-X" eventually turns into a smeared coating that actually makes vision worse.

Answer:
I like Rain-X in the summer; it makes it easier to clean the bugs off of the windshield. I don't use it in the winter; it seems to smear too easily.
Good point about changing wiper blades frequently. I'd also recommend that you go with winter blades; the ones with the flexible rubber boot that covers the workings of the blade. It doesn't take long for summer blades to freeze stiff from an accumulation of snow/ice and become all but useless.

Answer:
I agree with Phil on RainX. It is one of the best bug preventatives around. It works good with Love Bugs. I also recomend winter wipers with the rubber boots. No matter how new the wipers are they can freeze very quickly. I have had to stop plenty of times to knock the ice off them.
Pretty good advice, keep them new and replace often. It's an easy safety measure you can do quickly.

Answer:
...and while we're on the subject....
NEVER use "summer" washer fluid in the winter. Buy lots of "winter" fluid and squirt it up there frequently when you've got road spray. Make sure the label says something like "-20 degrees" or "winter formula". But be forwarned -- even these supposed "winter" formulas will freeze as they hit the windshield if it's cold enough and you're going fast.
There's nothing scarier -- almost nothing -- than squirting washer fluid on your windshield and watching it instantly freeze into an opaque glaze you can't see through. This can happen easily when the temperatures dip down to 20, 10, 0 or -0 etc.... And it happens at high speed -- when it's most dangerous -- because the 50+ mph cold airflow on the outside of your windshield keeps the glass itself below freezing temperature. It takes a lot of defroster heat to warm the windshield enough to keep fluid and spray from freezing. I dump some plain-old rubbing alcohol into the fluid when I know I'll be driving in extreme cold, and keep lots of air directed to the defroster vents to keep the windshield warmer than the outside air.
"Frozen fog" is sometimes a problem in winter. It sticks to your windshield and it won't wipe off unless you've got your windshield warm. Again -- pumping lots of warm air from the defroster vents BEFORE you hit frozen fog, and having a winter formula washer fluid ready to spray up there.....it beats driving blind till you can find a place to pull over.....if you CAN see to pull over....

Answer:
Well since you brought up the subject.
Many people think their wiper blades are bad when in fact they are only dirty. They put on new wiper blades and they work great for a few weeks and then start streaking and smearing again.
Make it a practice of wiping down your blades. Flush the frame with water and wipe the rubber with damp towel a few times. Water is best, wiper fluid is 2nd best. Do not use alcohol on your rubber wiper blades as this only dries them out and causes the blade to deteriorate faster.
Answer:
uturn2001 -- my accomplice in newbie advice -- is right again. Except.....I'd rather throw them away than clean them. It's faster, easier and after "a few weeks" they only have a few more weeks life left in them anyway. They're cheap to the company (very cheap) and ever since I starting collecting them like trip envelopes and changing them on a whim without regard to cost/waste, I've never (and I mean never) had a problem with streaking or blurring.

Answer:
Clean your blades edges with ALCOHOL wipes you will surprised at the amount of dirt that builds up on the edges , no need to buy new blades evey few months , twice a year is MAX but when you do buy the good ones,
Summer is actually harder on your blade edges than winter

Answer:
I use the -40 washer fluid. You usually have to go to one of the better stores to buy it, and it costs about $4/gallon. Prestone winter fluid works great, and Sears carries it.
Canadian Tire up in Canada (no surprise there...) used to have the best winter fluid. It was good for something like -50!
If you can't find fluid that works good in low temperatures, you can always add isopropyl alcohol to the fluid. I used to do that when I drove in Quebec.
Answer:
I get the CANADIAN TIRE -50 with TEFLON whenever I get to Ontario. Helps clean off the darn liquid calcium they use in places up there for ice / snow control ( AKA Greasy Slime )

Answer:

That's the problem I think. My company issues the cheap ones. They have hoods over the mechanism, but I think my Schick disposable has thicker blades than those wipers. They really are shot after a couple months. I've bought them on the road a couple times (reimbursement) but those didn't seem to perform much better. But I agree-- if you're buying blades, the better blades keep a sharp edge longer..

Answer:
If you REALLY want to get your windshield clean use Bon Ami cleanser or fine rubbing compound diluted with water. It will clean off all of the gunk film and let you get down to the glass.