The phrase "a notable addition" is correct and usable in written English.
You can use it to describe something that is significant or worthy of attention when referring to an addition to a group, list, or collection.
Example: "The new software feature is a notable addition to our product lineup, enhancing user experience."
Alternatives: "a significant enhancement" or "an important contribution".
The researchers estimate the global production of vesicles by Prochlorococcus alone at a billion billion billion per day — representing a notable addition of carbon to the scarce nutrient pool of the open seas.
One of video's special niches -- outstanding films seen by relatively few -- gains a notable addition today.
And, to London's treasury of remarkable if bizarre spaces, the black tetrahedron is a notable addition.
Vegetables and fruits feature prominently, and many dishes come with a notable addition of nuts and grains.
In a notable addition to Euclid, he tried valiantly to prove the parallel postulate (discussed later in Non-Euclidean geometries).
In chronicling the animosities between Russia and England, Cumming provides a notable addition to the accounts of the Cambridge spies.
That'll make Jumo a very notable addition to a fintech scene that is already showing significant potential across the Asian region.
A second notable addition to the revamped website is the TRIPups feature, which are a special type of activity.
Miller, a less notable addition in Miami's summer free-agent coup, had seen his playing time and shot fluctuate throughout the regular season.
SkyDrive is a pretty notable addition to the Windows Phone marketplace, as similar online file storage services like Dropbox and Box.net haven't yet found their way to Microsoft's mobile OS.
The Venite was performed on 13 June 1923 at the Queen's Hall, by the Philharmonic Choir under Charles Kennedy Scott; the Spectators critic thought it a "very notable addition to modern British music".
