The OED issues a review every quarter listing the new and revised entries for that quarter. Recently editors have worked mostly on words beginning re- so there are a lot of new verb entries beginning re- eg redefend, redeliberate and refinish. Just because the word has only just entered the OED for the first time, this does not mean that the word itself is new. The first citation for refinish is 1773. A lot of entries containing 'red' have been added too, eg red wine vinegar. This is another old term, although it was not in the dictionary before; there is a citation from 1597.
Apart from words beginning R, other new entries include:
anyhoo: variant of 'anyhow'
c'est la vie: French for 'that's life' but with the definition "expressing resignation at, or acceptance of, things as they are"
clonable: that can be cloned
dot-org: internet address
First Nation: North American peoples of Canada
globaloney: nonsensical talk concerning global issues
soundclash: piece of music with contrasting elements
toasted cheese: self-explanatory
unmixed blessing: wholly advantageous situation or thing
warm-down: cooling-down session after exercise
waterboarding: interrogation technique which simulates drowning
wire transfer: method of transferring funds
You can read the Chief Editor's report and the full list of the new and revised entries on the OED website. Remember that virtually all UK libraries subscribe to the online version of the OED and your library ticket will give you access (ask your librarian for a PIN number if necessary - it's a fantastic resource available free of charge to library members).