After the Samsung Galaxy S 2 launch announcement, I made an educated prediction that the T-Mobile variant would come with a Qualcomm SoC and not Samsung's own Exynos. The combination of no hands-on, T-Mobile's desire to have a DC-HSPA+ phone for its DC-HSPA+ network, and also talk of the Samsung Hercules all clued us in. Further, to use Qualcomm's MDM8220 would necessitate use of a Qualcomm SoC to enable voice. Just as we predicted, Samsung today indirectly confirmed our suspicions by tweeting that the T-Mobile SGS2 will indeed include a 1.5 GHz Qualcomm APQ8060 SoC. The GalaxySsupport account purports to be official Galaxy S support for Samsung. 

As a reminder, the APQ prefix in Qualcomm's lineup denotes an AP-Only (only the Application Processor inside) SoC, with no cellular baseband. The reason for the T-Mobile variant including an SoC without baseband is that it is highly likely to include an MDM8220 for DC-HSPA+ connectivity, which would make it the first shipping DC-HSPA+ enabled smartphone. 

Source: GalaxySsupport