...The company is taking a "strategic action" against a new competitor which relates to preserving their current employees and market, and actually has nothing to do with you personally, so don't take it personally and don't do anything rash to escalate things. Note to self: when you leave a current employer, you're "taking some time off" so they don't know where you're going. Looking at this from the leaving-employer's perspective, they don't want their best IT staff looking for jobs at this new company with you as the conduit, so they fired a "warning shot", which is what all the stuff they said (but didn't do) was about. It worked well for them, since your leaving-employer's name was on your post ;-). From the gaining-employer's perspective, they don't want to get an employee and a lawsuit at the same time (not even one with no merit). From your perspective, you don't want to spend a bunch of $k down the lawyer rathole, and if you think your previous employer is a bugger, wait until you see your legal invoices for chatting about your problem for the 3 months it will drag on. So if no suit is filed, and if you decide to hire a lawyer, just get advise from him on reviewing the letter below you write - don't let him send letters to your former employer, as they will then have to spend $ to have their lawyer reply, which will actually make them mad, as opposed to the posturing they are currently doing.
So far, there is only a threat to sue you and to sue your employer, (and a posting on slashdot that identifies the threatening employer). Best to say and do little and just ignore and start in at your new job.
If the leaving-employer actually files such a suit (which is unlikely), then hire an attorney (wouldn't hurt to interview _but_not_hire_ some attys now).
In any event, you should pre-emptively write a letter to your leaving-employer simply stating that you have taken nothing that belongs to the leaving-employer: code, customer lists, or any other property or "proprietary information", and thank them for the years of mutually enjoyable service. You might also point out that as of now, you are undamaged by their unfounded threats, but if those threats cause you to lose your job with your gaining-employer, you would look to recover those damages from them, and it would be in everyone's interest to let the matter drop.
If the leaving-employer files and serves an action anyway, or the gaining-employer renegs on their offer because of the threat/action, then sit down with some reporters for local and national media, and describe the situation, and how you were left jobless by your bullying leaving-employer.
If you're looking for a silver lining, consider that your mere leaving (and maybe some unsaid other things) has caused your leaving-employer to see you singularly as a threat to their entire business, which is a compliment, indeed!
-from someone who has been in your shoes a few times.
