The 31 members of the OECD today voted today to accept Estonia, Israel and Slovenia, which will thus become country members 32, 33 and 34. (The list of the other 31 is here).
The Economist often characterizes the OECD as "a rich-country think tank". While I doubt Israel's accession will make any difference in anyone's immediate day-to-day life, it's a nice club to belong to, and being inside is nicer than being outside.
The Palestinians did their best to prevent Israel being accepted, on the principle that anything that's good for Israel must be very bad. It seems however that the decision reflected actions and their expression in numbers, not ideology, so the Palestinian efforts didn't make any difference. The OECD press release announcing the decision (linked above) notes that "Israel’s scientific and technological policies have produced outstanding outcomes on a world scale."