Going by the observations of UBS Investment research analyst Maynard Um, the first-day demand for Apple’s newly upgraded, Tuesday-released MacBook Pro notebooks lineup – comprising 13-inch, 15-inch, and 17-inch MacBook Pro models - was ‘strong.’

Um, who checked up the sales status of the new MacBook Pro line at different Apple stores, reported that the Apple had already sold out the new MacBook Pro line’s Core 2-Duo equipped 13-inch version, which features the Nvidia GeForce 320M - a graphics processor particularly designed for the low-end MacBook Pro notebook.

There are two models of the 13-inch MacBook Pro – one priced at $1,199 and featuring 2.4 GHz Intel Core 2 Duo and 250GB hard drive priced; and the other a $1,499-priced model featuring 2.66 GHz Intel Core 2 Duo and 320GB hard drive.

Commenting on the Tuesday-released MacBook Pro upgrades, Um said: “Apple should benefit from the refresh, as it positions it for share gains heading into the education spending & back to school season, & we see continued Mac momentum as a key driver of upside to estimates.”

Um’s report is further substantiated by AppleInsider’s checks with authorized resellers, which reveled that while the high-end 15- and 17-inch MacBook Pro models are in stock, most of them have sold out their stocks of the 13-inch model.