In addition to the "thanks for not quitting" bonus at the end of the year, you might as well leverage for better benefits in the interim: you are, after all, going to have to be paying for your own health, etc all too soon.

First thing I'd tell them is that you're switching to whatever schedule you damn well please: 4 day week, or 10am start time, whatever floats your boat.
Next would be: they need to pickup the full health/dental/vision premium if they aren't already. They should also pick up the premium for Aislinn, as a good-faith gesture to inspire you to stick around, and do so happily.

You should also be cleared for a healthy budget to hire pro temps and make sure you hit their deadline without being forced into OT: you'll need your after-work hours for job-hunting after all, and it would be unfair, selfish and rude as fawk for them to presume you'll turn in 60hour weeks when you effectively have a pink slip in one hand / are facing a job market where the average job hunt is 12 to 18 months. (If you ONLY accept the 'fair retention bonus' and they pillage you with last minute changes, extra hours, etc and you alter the agreement/leave in disgust at that point, who is holding the proverbial bag?)

You're, after all, talking about not only losing your job/ having to start job hunting, but REALLY you are not able to start the job hunt until after their dec 2010 deadline, since you wouldn't be able to say YES to the perfect NEW job if they (a potential new job) want you to start in November.
Minimum self-protection: portion out the retention bonus: 10% at end of sept, 10% at end of oct, 10% at end of nov and the rest at the end of the year.

Note also what this whole thing is going to look like to your next employer: IMO You might as well stamp "doormat" on your resume rather than explain what really happened when you left/your team got laid off.

That said, you must be a rockstar if everyone else got axed and you got the engraved 'please stay' invite. Good luck!

Oh, and capicola is right: there could be substantial tax savings in getting that bonus check dated 2011. Nice point!

They didn't seem too open to negotiation. If I don't agree to their terms, they seem pretty willing to terminate me immediately and try to make it work with the people they have for 2 months.

I won't be wanting a reference from anyone left at the company. The one person I'll want a reference from left a few months ago.

As for hiring temps, I don't think I'll be overworked and shouldn't need additional help. The things I'm doing would also require a lot of training for a temp, so I don't think it's worth it. I don't predict having a solid 5 months of hard work ahead of me. There are just some time sensitive things that they'll need me to work on near the end of the year.

I don't think my career momentum is necessarily in jeopardy. The company has an open leave policy, I will still be able to take regular sick days and vacation days, so I think I'll be able to look for jobs in the last few months of the year with the caveat that my earliest possible start date is in 2011.

I also wondered whether it would look better to my future employer to quit or stay on. I decided that it doesn't actually matter that much, because I don't have to disclose the details. I can just say that I'm getting laid off beginning of 2011.

Even if I can't find anyone that will wait for 2011, isn't that what the retention bonus is kind of for?

I already start at 10, and with everyone gone in the office, I think after 2 months I'll get to start working from home a lot if not permanently.

This is actually kind of strange, because I was looking to quit and they actually want me to stay longer than what I wanted. Under those circumstances, when they throw in the bonus, it kind of just seems like free money for not a lot of extra headache.

Well, I suppose: There's also the outside possibility there'll be an upturn at the Company, and you'll be the lone person both with a pink slip AND able to keep his job.

I would keep my current salary and benefits until the end of the year, and would receive the retention bonus at the end of the year if I don't resign before then.

They've already offered me a number, and I'll probably take it. I was just trying to get an idea of whether what they offered is fair. Doing some further research online, it seems like it could vary depending on the position and situation, but I think I gave most of the important details.

If you do decide to counter, be sure to think of all the potentially negative effects of staying with them, and then bring them up during the discussion. A few that I can think of: no future with company, having to find a job right after the holidays, having to bridge income and health insurance for (possibly) several months until you find a new job. Lay it on thick.

Additionally, you should milk your remaining time. Not that I'm suggesting you act unethically, but it's reasonable that finishing the job might take a bit longer without your staff. In other words, this job might actually last longer than the rest of the year.

I mentioned this below, but I was actually looking to quit. I would feel weird pretending like I wanted a future at the company.

I also mentioned this below, but I don't think I'll have a full crazy schedule for 5 months. I don't have all the details of the transition, but I think the reason for the beginning of 2011 date is that there are some time-sensitive tasks they will want me to do at the end of the year.

I will have insurance until the end of January, and I'm willing to pay for COBRA for a couple months. With severance and retention bonuses they are offering, it shouldn't be difficult to bridge my income for a few months.

Looking for a job is actually the worst part. I think I can still look for a job near the end of the year, with a 2011 start date, using my regular sick time and vacation time.

Just please remember the job market is in a hurtful place: you will be very very lucky indeed if it's only "a few months" and not 12-18 months. Hopefully your wage is great at the current place and you've been there FT for years, and then you might qualify for maximum UI benefits (about $1900/month).