The specs for Intels Celeron-Skylake-processors have appeared on-line at multiple sources. The new Celeron socket 1151 CPUs will get the series numbers G3900 and G3920, both get a 45 Watt TDP.... Specs Skylake Celerons G3900 and G3920 Have Surfaced
Those CPU's are very good for their purpose, i have only good experience with last few generations of Celerons.
BCLK overclocking is all but useless since sandy bridge. It's tied to the iGPU and PCI lanes and can't really be touched.
BCLK oc is no more usefull since 2 or 3 gen of CPU (and wasn't too efficient in OC anyway). i always liked the Pentium/Celeron brand it's always usefull and not expensive product and with time it get really powerfull (i mean for price of course lol).