Evidence of Samsung's new Galaxy Tab 5 tablet comes from the Zauba website. This is the site that keeps track of imports and exports into India. On December 22nd, Samsung imported the SM-T555 tablet into the country for research and development. While it was made clear that this slate was not being offered for retail sale, it was valued at the equivalent of $354 USD. The next day, Sammy imported the SM-T116 tablet into India for testing. The 7-inch slate is to be destroyed after the testing is completed. 30 units, valued at $101 USD each, were brought into the country.
The best way to figure out what these devices could be, is to compare model numbers. The Samsung Galaxy Tab 4 10.1, which was released in May of this year, consisted of model numbers SM-T530 (Wi-Fi), SM-T531 (3G and Wi-Fi) and SM-T535 (3G, 4G and Wi-Fi). Compare the latter number with the SM-T555 seen on the Zauba site, and we are probably looking at the Samsung Galaxy Tab 5 10.1, powered by Android 5.0 and featuring the 64-bit processing capability of the Snapdragon 410. We could see a May or June release for the tablet.
According to the GeekBench website, the SM-T1116 appears to be an entry-level slate powered by a quad-core 1.2GHz Speadtrum SC8830. 1GB of RAM is inside with Android 4.4.4 pre-installed.
source: Geekbench (translated), Zauba via TechTastic (translated)