Right. Let's say I was searching for a job, but doing Rails work on the side (not a startup per-se, but you know... doing startupy like work). I could spent 1 day per week looking for a job, and 4 to 6 days a week coding for people. All the proceeds go into a consulting firm which I hold ownership of.
If you do this you are probably violating the unemployment rules in your state[1]. If you reported this income with the unemployment office you will most likely have your benefits reduced or eliminated. But most people don't report this income and get away with "double dipping" which was heretofore not allowed. Technically if the government found out you did this they could penalize you retroactively. But this is a hassle and most people just get away with it unnoticed.
Even more technically, some states will even deny unemployment benefits if you are working without pay such as in a startup situation (and you are honest enough to admit this). It's not about income or full utilization, it's are you working at all.
The change in the law makes getting paid for self employment legal. Although if your self employment included revenue I assume it would still count against the amount you received from unemployment, again depending on your state.
But yes, it is good for this to be official now.