We are truly excited about Windows Server 8, because the more users are using Hyper-V, the more market we have to sell our tools too.
As far as some features being included in hypervisors for free, that is not a concern to us. For example, free VMware Data Recovery released 2 years did not affect us at all, despite most of our partners and users also thought that "the sky is falling on Veeam" after the product was announced. Likewise, Hyper-V replication is as good as any free product - it has its limited use, but you would not rely on it beyond small Hyper-V deployments. As always, everything may look great on paper, but the devil is in details.
Even without deep testing, I have already compiled quite a long list of its implications comparing to our replication. To give you just one example: enabling Hyper-V replication on a VM doubles its write I/O (as every changed block has to be written to two places now, actual VHD and replica journal). Of course, this is totally acceptable if you only have a few VMs in your production, and are replicating may be 1 or 2 of those. Now, imaging the performance impact doubling your write I/O on multiple VMs (impact on both VMs performance, and your production storage performance). Do you think many people will choose to go with something that, for certain workloads, would require essentially doubling IOPS capability of your storage infrastructure (to keep the same SLA) when replicating majority of your VMs? While the actual replication may be free, what about the cost of storage upgrade?
Also, on an unrelated note - you may not know this, but most the core of Veeam management team comes from Aelita software (2 time Microsoft ISV Partner of the Year, acquired by Quest Software in 2004). Aelita's business was all about building paid alternatives to free Windows management tools provided by Microsoft (migration, backup, etc). It has been an extremely successful business, despite pretty much EVERY tool we produced had a free alternative from Microsoft. Does it prove that we know what we are doing as an ISV?
And, of course, you are spot on that we at Veeam are determined to keep pushing the envelope. As I mentioned, our last year's v6 release already has a long list of major advantages over yet unreleased Hyper-V replica. But, by the time Windows Server 8 is actually available, we will have v7