There are obviously security concerns with travelling to Israel and travellers should prepare themselves beforehand, but generally there are no official warnings against travelling there. There has been a ceasefire since November 2012 of the fighting in and near Gaza, but travellers are still advised not to go near Gaza or the border with Lebanon. More generally, there are high levels of unrest in the West Bank area, and especially around the illegal Israeli settlements in Palestinian territory.
Elsewhere in Israel, people do travel freely for business and leisure, but there are a lot of restrictions and checks because there is always the possibility of a terrorist attack, especially in the big cities. A recent attack in Tel Aviv injured almost 30 people. If you visit the larger cities you are advised to be on the alert, especially if you travel by public transport.
You should get an update on the situation before you go, from your embassy or other reliable source, but you can start with these general tips for travellers.