Mods, if this really should be in IMHO, my feelings won’t be hurt if y’all move it.
Is two weeks’ notice still considered decent for most purposes? I’ve been with the same job for over six years, and was [once] quite highly regarded. It’s professional type work, and training a replacement may take a while.
So to leave no hard feelings… is two weeks too short?
In the US, two weeks is considered to be the norm. I would have no problem with it. If you situation allows and if you wish to, then 4 weeks is even better.
Apologies if a reply from the other side of the pond is not much use, but here we are more likely to think that if you are paid monthly, your notice must be one month (perhaps more IF by mutual agreement), perhaps less again if by a friendly agreement if you get on well with your personnel officer. Jobs where you are paid weekly, one weeks’s notice and so on.
Whatever, it sounds as though someone has a nice shiny new job to go to , so congratulations, and best of luck! 
(Anyway, doesn’t your contract of employment specify the period of notice to be given/observed both by you and your pointy-headed boss?)
Two weeks is the norm but technically you do not need to give any notice and can just walk away (barring any contractual obligations). The two weeks notice is more to not burn any bridges by allowing a little time for transition. Of course, depending on what you do, projects you are currently involved in and so on it may be that more than two weeks would be needed.
The flip side is what your next employer is willing to tolerate before you come work for them (assuming you are going to work for someone else). Most employers are happy to grant the two week gap till you start with them but asking for more time may be an issue with them.
In the end do the best to keep all parties as happy as possible. Even with an employer you’d just as soon give the finger to and walk away from it is best to avoid bad blood. In the end I would do what is right for you and your new employer and work the old employer in as possible.
If your current employer terminates your employment immediately, will you be able to start in your new position ahead of time? It’s my understanding that your current employer can well turn around and offer you two weeks pay in lieu of notice and ask you to leave immediately.
If that won’t cause undue financial hardship on yourself and would allow you to not burn any bridges behind you, 4 weeks notice is certainly a nice thing to do out of respect to your employer. How this reconciles with your (former) highly regarded status is eomthing only you can determine though.
Good luck in your new position!
The one time I quit a job I gave long notice. I was leaving after Christmas and I think it was before Thanksgiving that I told my boss. I did it because I knew there were a lot of things that would need to be taken care of before I left and didn’t want to leave them in a bind. On the down side of this, I pretty much took care of that all early-ish, and the last week and a half I was there I didn’t have much to do, as all my work had been delegated already. Two weeks feels quick though, I think, unless I was worried about my employer dropping me as soon as I told them I was leaving, I’d give three weeks notice, but that’s my own personal comfort zone.
On an unrelated tangent, I’m reading The Neverending Story for the first time right now, and I get your username now.
I worked construction as a pipefitter for about 15 years, until 1987. Then the norm was, “Fuck it, get me my money, I’m out of here!”
I just gave two weeks notice about three weeks ago. It was on a Monday. Once I sent in my letter I received a call from my manager telling me he was sorry to see me go and thanking me for giving enough time to get a temp replacement trained. On Tuesday morning, the next day, I was quickly ushered into the manager’s office and was told there were numerous complaints about me stretching back six months. I was asked to collect my personal effects from my cube and to leave the premises immediatley. I asked if I would still get paid for the next two weeks and was told no. So I collected my stuff, said good-bye to co-workers I wasn’t going to stay in touch with and left. The upshot was I got to start my new job early. The downshot was I was out of work for about a week. Oh well.
Since this IMHO… your situation sounds good. You’ve worked there a long time, and are a respected professional. Therefore, it is hoped you have little to fear if you give a longer notice. They are unlikely to let you go early or anything like that. If you believe this is true, I would give them a longer notice. IMO, it is (1) the right thing to do, and (2) if you have built anything good in six years, you will take pride in seeing it transferred correctly to someone else, and only you have the tools to train/document your job.
As an employer myself, I appreciate getting a two week notice from my staff. It gives me time to figure out other personal matters such as final checks, benefit termination/extention with COBRA notices, paperwork completion, getting forwarding addresses if necessary, etc.
At-Will employment does not mean that a two week notice is necessary, but it is a good policy to follow. If someone gives us a two week (or longer) notice and is an employee in good standing, we tell them that they are more than welcome to reapply if they find themselves back in town or lost another job elsewhere. I’ve had about 10 people take me up on that offer, and they were quite happy about that extra level of security.
Since I value a two week notice, we in turn allow our new hires to give their previous employers two weeks notice as well, if they wish to. Not all employers do that though. If you have an employer who expects a two week notice but yet expects people to start work the next day at his/her whim, that is a good sign of poor management and that place of employment should be avoided…it is usually the tip of an iceberg of problems.