Great question, Feliza! I think having strong loyalty is a good thing, but I think you should also be fair to yourself. In the end, they are the ones cutting off the relationship, not you, so if you feel you have to leave beforehand, then I think that would be fair. However, even if it is fair, you might be burning bridges as a result. The problem is that the new management may choose not to retain anyone from the former company, so it isn't as if you are in a completely safe situation. Many times, companies give employees special bonuses to stay on during the transition to mitigate this issue, and it's too bad they didn't do the same here.
If you have a really good relationship with your current company, it might be a good idea to have a frank conversation with them, telling them that you are concerned that any new company may not keep you on board, or if they do, whether it will be a good company to work for. And if they don't keep you on board, then suddenly you will be stuck without a job. At the same time, you love your company and don't want to leave them in the lurch, so do they have any ideas to help with the situation? Maybe they'll bring up the idea of a stay-on bonus, or maybe there is some other option out there.
I could be wrong about that advice, however, so it will be interesting to hear other's opinions on this. My guess is that being frank with them has few negative possibilities - they are not going to fire you right as they are trying to sell it - that would be a disaster for them. So my guess is that you are in safe territory by bringing it up, but I'm not completely sure.