clarify

Signed-off-by: Michael Crenshaw <350466+crenshaw-dev@users.noreply.github.com>

README.md

@@ -43,7 +43,6 @@ Participation in the Argo CD project is governed by the [CNCF Code of Conduct](h
 ### Blogs and Presentations
 
 1. [Awesome-Argo: A Curated List of Awesome Projects and Resources Related to Argo](https://github.com/terrytangyuan/awesome-argo)
-1. [Unveil the Secret Ingredients of Continuous Delivery at Enterprise Scale with Argo CD](https://blog.akuity.io/unveil-the-secret-ingredients-of-continuous-delivery-at-enterprise-scale-with-argo-cd-7c5b4057ee49)
 1. [GitOps Without Pipelines With ArgoCD Image Updater](https://youtu.be/avPUQin9kzU)
 1. [Combining Argo CD (GitOps), Crossplane (Control Plane), And KubeVela (OAM)](https://youtu.be/eEcgn_gU3SM)
 1. [How to Apply GitOps to Everything - Combining Argo CD and Crossplane](https://youtu.be/yrj4lmScKHQ)
@@ -51,10 +50,8 @@ Participation in the Argo CD project is governed by the [CNCF Code of Conduct](h
 1. [Automation of Everything - How To Combine Argo Events, Workflows & Pipelines, CD, and Rollouts](https://youtu.be/XNXJtxkUKeY)
 1. [Environments Based On Pull Requests (PRs): Using Argo CD To Apply GitOps Principles On Previews](https://youtu.be/cpAaI8p4R60)
 1. [Argo CD: Applying GitOps Principles To Manage Production Environment In Kubernetes](https://youtu.be/vpWQeoaiRM4)
-1. [Creating Temporary Preview Environments Based On Pull Requests With Argo CD And Codefresh](https://codefresh.io/continuous-deployment/creating-temporary-preview-environments-based-pull-requests-argo-cd-codefresh/)
 1. [Tutorial: Everything You Need To Become A GitOps Ninja](https://www.youtube.com/watch?v=r50tRQjisxw) 90m tutorial on GitOps and Argo CD.
 1. [Comparison of Argo CD, Spinnaker, Jenkins X, and Tekton](https://www.inovex.de/blog/spinnaker-vs-argo-cd-vs-tekton-vs-jenkins-x/)
-1. [Simplify and Automate Deployments Using GitOps with IBM Multicloud Manager 3.1.2](https://www.ibm.com/cloud/blog/simplify-and-automate-deployments-using-gitops-with-ibm-multicloud-manager-3-1-2)
 1. [GitOps for Kubeflow using Argo CD](https://v0-6.kubeflow.org/docs/use-cases/gitops-for-kubeflow/)
 1. [GitOps Toolsets on Kubernetes with CircleCI and Argo CD](https://www.digitalocean.com/community/tutorials/webinar-series-gitops-tool-sets-on-kubernetes-with-circleci-and-argo-cd)
 1. [CI/CD in Light Speed with K8s and Argo CD](https://www.youtube.com/watch?v=OdzH82VpMwI&feature=youtu.be)
@@ -63,7 +60,6 @@ Participation in the Argo CD project is governed by the [CNCF Code of Conduct](h
 1. [Introduction to Argo CD : Kubernetes DevOps CI/CD](https://www.youtube.com/watch?v=2WSJF7d8dUg&feature=youtu.be)
 1. [GitOps Deployment and Kubernetes - using Argo CD](https://medium.com/riskified-technology/gitops-deployment-and-kubernetes-f1ab289efa4b)
 1. [Deploy Argo CD with Ingress and TLS in Three Steps: No YAML Yak Shaving Required](https://itnext.io/deploy-argo-cd-with-ingress-and-tls-in-three-steps-no-yaml-yak-shaving-required-bc536d401491)
-1. [GitOps Continuous Delivery with Argo and Codefresh](https://codefresh.io/events/cncf-member-webinar-gitops-continuous-delivery-argo-codefresh/)
 1. [Stay up to date with Argo CD and Renovate](https://mjpitz.com/blog/2020/12/03/renovate-your-gitops/)
 1. [Setting up Argo CD with Helm](https://www.arthurkoziel.com/setting-up-argocd-with-helm/)
 1. [Applied GitOps with Argo CD](https://thenewstack.io/applied-gitops-with-argocd/)
@@ -73,3 +69,10 @@ Participation in the Argo CD project is governed by the [CNCF Code of Conduct](h
 1. [Getting Started with ArgoCD for GitOps Deployments](https://youtu.be/AvLuplh1skA)
 1. [Using Argo CD & Datree for Stable Kubernetes CI/CD Deployments](https://youtu.be/17894DTru2Y)
 
+### Vendor-sponsored community resources
+
+The following links are to resources hosted by Argo CD vendors (companies which use Argo CD as part of their software offerings). 
+These resources are vendor-neutral (overwhelmingly _about_ Argo CD, but may briefly mention the vendor) and do not require providing information for marketing purposes.
+
+1. [Unveil the Secret Ingredients of Continuous Delivery at Enterprise Scale with Argo CD](https://blog.akuity.io/unveil-the-secret-ingredients-of-continuous-delivery-at-enterprise-scale-with-argo-cd-7c5b4057ee49)
+1. [Argo CD Sandbox (demo instance)](https://argocd.argo.opsmx.net/) (requires logging into the demo instance with a Google account)