Actually there's a good chance the GS2 will be better than the Targa anyway. Hard to say whether Exynos is better than OMAP4, as the latter is not out yet. Exynos is better on paper than Targa 2 in most every way, it just doesn't have the driver development yet since its so new. Both have 2 Cortex-A9 cores with NEON, while Tegra 2 is an A9 but does not have hardware NEON support. So they should be very similar, Samsung may actually have the edge if they manage to avoid the firmware and driver issues that plagued the first galaxy s.
Its unlikely that the Targa will have a comparable screen to the beautiful S-AMOLED+ on the GS2, especially if its rushed to market earlier to fill the gap left by the Etna-Bionic, again if it is even cancelled. TouchWiz 4.0 is actually looks pretty cool from what I've seen, and Samsung tends to release the source code for all their devices, making custom ROM's an easy option. MotoBlur, however, shows no signs of being any more useful, and MOTO likes to lock and encrypt their bootloaders, making hacking them difficult. I haven't heard anything to support the idea that the Targa is unlocked other than wishful thinking. Other than that, everything else seems pretty similar, with a possible aesthetic advantage to Samsung and a durability advantage to Moto, based on current and recent devices.
Not saying that the GS2 is better or worse, we still know very little about the Targa, or if in fact it actually exists in the form we believe it to. I agree Samsung has had their issues in the past. But if they get a superior dual-core LTE device to the market before Moto, or around the same time, I see no reason not to get it unless it appears to have similar issues to their earlier phones. Samsung is an enormous company, and they certainly have the wherewithall to have addressed and corrected the software issues they had in the past, after seeing how it affected sales.