Whether it be talking with friends, relatives, or just casual acquaintences, if the subject of politics comes up, I have noticed very specific behavior patterns between those who tend to be left of center politically versus those who are right of center. 

There are plenty of things that annoy me about political conservatives too but not as consistently as "regular" people who are politically left. The list below is not a list of annoyances of politicans or public figures but rather traits of left of center people I have met in real life that seems to come up over and over.

So here's my list of things that bother me about dealing with political leftists:

1. Choose their positions based on emotion and passion rather than through research or investigation
2. Rarely look up for themselves the underlying facts on a given issue but rather rely on "trusted" advisors or editorials
3. Are very intolerant of views that do not match theirs. I don't think I've ever seen a conservative say "I don't want to hear anymore, let's talk about something else".  by contrast, over and over, liberals will (at best) ask you to change the subject because they don't want to hear other points of view or (at worst) try to bully you from giving an opposing point of view.
4. Act as if their positions have some sort of moral high ground simply because their positions are based on "good intentions".
5. Similar to #4 -- take the view that their position is the "civilized" or "moderate" point of view. And that other points of view are simply barbaric "Of course guns should be outlawed" or "You didn't vote for Kerry? You seem like such a smart guy."
6. Have no knowledge of the tax system even as they loudly advocate higher taxes on "the rich". There's nothing quite like seeing a 3rd grade teacher espousing how the rich pay hardly anything in taxes even as they are talking to someone they know pays immense amounts of taxes (because I usually make sure to correct this falacy).  And I usually get "Then you need to get a better accountant" as if they have any concept of the tax structure.  Oh yes, I'll just use the magic loopholes that liberals are so certain exist and avoid taxes...
7. Think that feeling strongly about something counts more than actually doing something.  My $1k contribution to the Cancer Society isn't as significant as someone who did a "Cancer walk" and got $315 in donations apparently.  And btw, it's nice to do a cancer walk, it's even nicer to donate money yourself. Walking, chanting, whatever may make you feel but but it does nothing. It's the people donating to the cause materially that are actually making a material difference.
8. Think that witty sarcasm is a substitute for a coherent argument for their position.  How many times have you made a point only to have a left winger try to dismiss it with a one-line sarcasm "Of course we armed Osama, I guess we got what we paid for.."  That's a non sequitor and stupid to foot.  But knowing little irrelevant pseudo-factoids is not a substitute for knowledge on the actual issue.  It really comes to a head if Iraq comes up. Most anti-Iraq "war" advocates can't put together a coherent argument against it.
9. Massively inconsistent, simple minded positions. There's nothing quite like having a friend in Southern California say "Wars never solved anything".  Really?  You plan to argue that southern California should go back to Mexico?  Because there was one war (US/Mexican) that most definitively and materially solved a particular question. Not to mention the Civil War and slavery, World War I, World War II, Korea, and Gulf War I.  Or some middle class person living in a house in Florida that they inherited from their father arguing for higher estate taxes (why wait? why not hand your house to the government right now?). Or my favorite "There's no excuse for anyone to go hungry in this country." as an argument for more welfare.  I agree there's no excuse, only a total dumbass could go hungry in this country. Welfare ain't gonna fix that. 
10. Problems are always to be solved by someone else.  To left wingers, being compassionate seems to mean being intellectually concerned about people but not wanting to actually do anything.  My uncle, a conservative, drove down to Louisiana as part of his church group to repair people's houses.  Meanwhile, not a single liberal I know has volunteered for anything but they sure have argued for more government spending on Katrina relief -- which is easy for them, I end up paying for it.
11. Believe in equality unless equality is inconvenient.  I try not to flaunt my material success but at the same time,  I am proud of what my family has achieved.  My wife and I started with nothing (and btw, yes you can live on minium wage -- I did).  But if I object to paying more in taxes, I am called greedy by some of my liberal friends.  If I ask if they want to compare how much they donated to charity last year (not taxes, charity) they always come back with the "well you have more to give" argument.  So what?  And I've even tried to do the "Okay, then as a percentage of our income comparison" I still get the "we don't have as much excess money to give as you do" argument.  And on taxes, even though I use the same roads, schools, police, etc. and pay literally over 50X more in taxes than most people and support progressive taxation, I still get implied arguments that I don't want to pay my fair share if I object to paying even more in taxes.
12. Obsess on diversity of skin color instead of diversity of ideas.  What is it with the left and their obession with skin color? Yet, as I mentioned earlier, liberals are incredibly intolerant of other ideas. They want to live in an echo chamber. Most conservatives I know enjoy a good intelligent discussion.  Most liberals get angry and frustrated with people who dare to have different (or incorrect) opinions.  I have one friend named Chris who is liberal who is the exception to this (so if he's reading, kudos to him) who will intelligently and thoughtfully discuss issues without getting angry.  I can't think of any liberal friend or relative who doesn't get angry and frustrated if confronted with opinons that don't match theirs.

Like I said, these are observations on public speakers. These are observations on friends, family, acquaintences that I meet and talk to.  I am often almost made to feel like I should be ashamed for having conservative..uncivilized view points. If only I were as enlightened like them and used my heart more I would be ready to be welcomed into their civilized society.