If you are talking in terms of months and years - you may lose your Israeli partner's interest. In this circumstance he may very well perceive you as not being serious. Try to meet him or her half way - try to speak realistically in terms of days and weeks. Meetings can be and are often spontaneous. Again a reflection of the informal and family oriented culture.
Punctuality is relaxed.
Always allow up to 15-20 minutes before thinking that your party is late. Even here, things are rapidly changing, especially in the hi-tech environment where many Israelis pride themselves on being on time. After work hours, you may notice a more relaxed tone. When setting work deadlines, be sure to leave some advanced buffer period. They see this time as being too valuable - instead suggest sandwiches and drinks to be brought into the meeting room.