The USCIS has completed its data entry for all H-1B cases selected in the recent H-1B lotteries and case processing is now underway. All unselected petitions will be returned during the next 30 days and the USCIS will make an announcement when all unselected petitions have been sent back.
By May 12, employers should see action on all premium filings, either in the form of an approval, an Request For Evidence, or a denial. Non-premium cases began processing on May 4 and will continue through mid-August.
There is no online system for determining whether a petition was selected. Instead, the only way to know with certainty is to receive either a filing receipt or a returned petition. Clearly, the USCIS could vastly improve this aspect of the process.