In NY whenever I do a Revocable Living Trust for a couple, we divide the assets and put half in one person's trust and half in the other person's trust. As A LAWYER correctly points out, there is no pat answer right for every situation. For example, sometimes one spouse is more apt to be sued than another spouse (ie. a doctor or business owner) and in that situation we may put more assets in to the trust of the spouse who it seems is less likely to be sued.
Jointly held Real Property can be split into the 2 trusts by deeding the property 50% each into the separate trusts as tenants in common.
You should consult with an attorney who is familiar with all of the facts specific to your estate planning needs before you act.