my local MC only stocked the G2120 earlier this week. I think the i3-3220 was out right after Labor Day as promised, the 3225 took a week later to arrive.
Very few benchmarks out there....think it will take a while to show, but honestly the only data to look for is temperatures and power consumption.
I think the expectation in this CPU is it replaces the G8xx series, and would be a bonus if the numbers can get close to a i3-2100
If you already have a G620/G630, it's probably not a big step up.
However, if I am building from scratch, a few considerations that could tip my decision towards the G2120:
1) support for DDR3-1600Mhz -> 2 steps above the G620. this would give a noticeable boost to the already crippled on-board graphics
2) potentially lower thermals -> based on mobile cpu benchmark number, dual core IVB will likely beat SB both in power consumption and temperature, maybe not by much but I think it will surprise some folks who used to read about those IVB overheating during overclocking under high voltages...
3) this one is controversial, but infrequently one hears about SB systems randomly "freezing". No one has found the definitive proof but some points the culprit towards the on-die memory controller and its incompatibility with certain memory . Again this is not validated and the "freezing" is difficult to replicate in a lab. No similar reports in IVB systems so far. I have purchased a G620 and a i3-2100 process in the past from MC and did not encounter this issue, but I do believe phenomenon is real.
having said that, at MSRP of $99, the G2120 is a bit overpriced as it does not offer HT and Intel quick sync
but for $79, I think the price is a decent processor, especially if one considers using in a small ITX system
If the sole purpose is to surf the web and stream multimedia w/o heavy gaming, the value of a $50 G630 is very hard to beat